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Sample records for suspension-cultured plant cells

  1. Somatic embryogenesis and plant regeneration from cell suspension cultures of Cucumis sativus L.

    Science.gov (United States)

    Chee, P P; Tricoli, D M

    1988-06-01

    A procedure for the regeneration of whole cucumber plants (Cucumis sativus L. cv. Poinsett 76) by embryogenesis from cell suspension cultures is described. Embryogenic callus was initiated from the primary leaves of 14-17 day old plants. Suspension cultures of embryogenic cells were grown in liquid Murashige and Skoog basal medium containing 5 uM 2,4,5-trichlorophenoxyacetic acid and 4 uM 6-benzylaminopurine. Suspension cultures were composed of a population of cells that were densely cytoplasmic and potentially embryogenic. Differentiation of embryos was enhanced by washing the suspension culture cells with MS basal medium containing 0.5% activated charcoal and twice with MS basal medium followed by liquid shake cultures in MS basal medium. Sixty to 70 percent of the embryos prewashed with activated charcoal germinated into plantlets with normal morphology. Embryos obtained from suspension cultured cells without prewashing with activated charcoal organized into plantlets with abnormal primary leaves. Morphologically normal plantlets were obtained by excising the shoot tips and transferring them to fresh medium.

  2. Lignans from cell suspension cultures of Phyllanthus niruri, an Indonesian medicinal plant

    NARCIS (Netherlands)

    Elfahmi, [No Value; Batterman, S; Koulman, A; Hackl, T; Bos, R; Kayser, O; Woerdenbag, HJ; Quax, WJ

    Cell suspension cultures of Phyllanthus niruri were used to study the lignan profiles and biosynthesis. Suspension cultures yielded two lignans: the new cubebin dimethyl ether (1) and urinatetralin (2), a new lignan from P. niruri, but reported earlier from P. urinaria. This is the first report of

  3. A phytochemical study of lignans in whole plants and cell suspension cultures of Anthriscus sylvestris

    NARCIS (Netherlands)

    Koulman, A; Kubbinga, M.E.; Batterman, S; Woerdenbag, H.J.; Pras, N.; Woolley, J.G.; Quax, Wim

    2003-01-01

    In the roots of Anthriscus sylvestris 12 different lignans were detected. Arctigenin, dimethylmatairesinol, dimethylthujaplicatin, podophyllotoxin, 7-hydroxyyatein and 7-hydroxyanhydropodorhizol have not been previously reported to be present in A. sylvestris. In the cell suspension cultures, which

  4. Quantitative proteome changes in Arabidopsis thaliana suspension-cultured cells in response to plant natriuretic peptides

    KAUST Repository

    Turek, Ilona; Wheeler, Janet I.; Gehring, Christoph A; Irving, Helen R.; Marondedze, Claudius

    2015-01-01

    Proteome changes in the Arabidopsis thaliana suspension cells in response to the A. thaliana plant natriuretic peptide (PNP), AtPNP-A (At2g18660) were assessed using quantitative proteomics employing tandem mass tag (TMT) labeling and tandem mass spectrometry (LC–MS/MS). In this study, we characterized temporal responses of suspension-cultured cells to 1 nM and 10 pM AtPNP-A at 0, 10 and 30 min post-treatment. Both concentrations we found to yield a distinct differential proteome signature. The data shown in this article are associated with the article “Plant natriuretic peptides induce a specific set of proteins diagnostic for an adaptive response to abiotic stress” by Turek et al. (Front. Plant Sci. 5 (2014) 661) and have been deposited to the ProteomeXchange with identifier PXD001386.

  5. Quantitative proteome changes in Arabidopsis thaliana suspension-cultured cells in response to plant natriuretic peptides

    KAUST Repository

    Turek, Ilona

    2015-06-30

    Proteome changes in the Arabidopsis thaliana suspension cells in response to the A. thaliana plant natriuretic peptide (PNP), AtPNP-A (At2g18660) were assessed using quantitative proteomics employing tandem mass tag (TMT) labeling and tandem mass spectrometry (LC–MS/MS). In this study, we characterized temporal responses of suspension-cultured cells to 1 nM and 10 pM AtPNP-A at 0, 10 and 30 min post-treatment. Both concentrations we found to yield a distinct differential proteome signature. The data shown in this article are associated with the article “Plant natriuretic peptides induce a specific set of proteins diagnostic for an adaptive response to abiotic stress” by Turek et al. (Front. Plant Sci. 5 (2014) 661) and have been deposited to the ProteomeXchange with identifier PXD001386.

  6. Regulation of Cytoplasmic and Vacuolar Volumes by Plant Cells in Suspension Culture

    DEFF Research Database (Denmark)

    Owens, Trevor; Poole, Ronald J

    1979-01-01

    Quantitative microscopical measurements have been made of the proportion of cell volume occupied by cytoplasm in a cell suspension culture derived from cotyledons of bush bean (cv. Contender). On a 7-day culture cycle, the content of cytoplasm varies from 25% at the time of transfer to 45% at the...

  7. Chitosan mediated enhancement of hydrolysable tannin in Phyllanthus debilis Klein ex Willd via plant cell suspension culture.

    Science.gov (United States)

    V, Malayaman; N, Sisubalan; R P, Senthilkumar; S, Sheik Mohamed; R, Ranjithkumar; M, Ghouse Basha

    2017-11-01

    Phyllanthus debilis Klein ex Willd. is wild medicinal plant used in the traditional system of medicine. This plant has been actively used for hepatoprotection and to cure many diseases including jaundice and so on; which leads to complete extinction of this particular species. Therefore, the chitosan mediated cost effective cell suspension method has been developed for the production of hydrolysable tannin. The hydrolysable tannins are the main therapeutically active constituents with antioxidant, anticancer, and antimicrobial properties. An in vitro cell suspension culture was optimized by adding chitosan for production of hydrolysable tannin. According to the growth kinetics, a maximum biomass of 4.46±0.06g fresh cell weight and 1.33±0.04g dry cell weight were obtained from the optimal suspension medium consisted of MS medium+0.5mgL -1 BAP+1.5mgL -1 NAA. Chitosan was treated at the stationary phase which leads to the highest accumulation of hydrolysable tannin compared to the untreated control. Hydrolysable tannin was observed and compared using HPLC at the Rt of 4.91 in both chitosan treated and untreated cells. This is the first ever report where use of chitosan has been done to enhance the production of the hydrolysable tannin in P. debilis using cell suspension culture technique. Copyright © 2017 Elsevier B.V. All rights reserved.

  8. Recombinant human IGF-1 produced by transgenic plant cell suspension culture enhances new bone formation in calvarial defects.

    Science.gov (United States)

    Poudel, Sher Bahadur; Bhattarai, Govinda; Kook, Sung-Ho; Shin, Yun-Ji; Kwon, Tae-Ho; Lee, Seung-Youp; Lee, Jeong-Chae

    2017-10-01

    Transgenic plant cell suspension culture systems have been utilized extensively as convenient and efficient expression systems for the production of recombinant human growth factors. We produced insulin-like growth factor-1 using a plant suspension culture system (p-IGF-1) and explored its effect on new bone formation in calvarial defects. We also compared the bone regenerating potential of p-IGF-1 with commercial IGF-1 derived from Escherichia coli (e-IGF-1). Male C57BL/6 mice underwent calvarial defect surgery, and the defects were loaded with absorbable collagen sponge (ACS) only (ACS group) or ACS impregnated with 13μg of p-IGF-1 (p-IGF-1 group) or e-IGF-1 (e-IGF-1 group). The sham group did not receive any treatment with ACS or IGFs after surgery. Live μCT and histological analyses showed critical-sized bone defects in the sham group, whereas greater bone formation was observed in the p-IGF-1 and e-IGF-1 groups than the ACS group both 5 and 10weeks after surgery. Bone mineral density, bone volume, and bone surface values were also higher in the IGF groups than in the ACS group. Local delivery of p-IGF-1 or e-IGF-1 more greatly enhanced the expression of osteoblast-specific markers, but inhibited osteoclast formation, in newly formed bone compared with ACS control group. Specifically, p-IGF-1 treatment induced higher expression of alkaline phosphatase, osteocalcin, and osteopontin in the defect site than did e-IGF-1. Furthermore, treatment with p-IGF-1, but not e-IGF-1, increased mineralization of MC3T3-E1 cells, with the attendant upregulation of osteogenic marker genes. Collectively, our findings suggest the potential of p-IGF-1 in promoting the processes required for bone regeneration. Copyright © 2017. Published by Elsevier Ltd.

  9. Establishment of Cell Suspension Culture and Plant Regeneration in Abrus precatorius L., a Rare Medicinal Plant

    Directory of Open Access Journals (Sweden)

    Mohammad Serajur RAHMAN

    2012-02-01

    Full Text Available A new protocol has been developed for cell culture and in vitro regeneration of Abrus precatorius that holds enormous potentiality for preparation of medicines. In vitro grown calli were cultured in Murashige and Skoog (MS liquid media in agitated condition fortified with 0.5 mg/l 6-Benzylaminopurine. Growth curve of cells revealed that the cells continued to grow until 12 days of culture and got the highest peak from day 6-8. Isolated cell was found to produce highest 8.2% calli when suspended on MS medium supplemented with 0.5 mg/l 6-Benzylaminopurine and 0.1 mg/l 1-Naphthaleneacetic acid. Callus derived from single cell produced highest number of embryo (25-28% cultured on MS medium fortified with 2.0 mg/l 6-Benzylaminopurine and 0.2 mg/l 1-Naphthaleneacetic acid. The bipolar embryos were selected and optimum shoot formation was recorded on MS medium supplemented with 2.0 mg/l 6-Benzylaminopurine and 0.1 mg/l 1-Naphthaleneacetic acid. The optimum root induction was noticed in MS medium supplemented with 1.0 mg/l 3-Indolebutyric acid. Rooted plantlets were successfully transferred to potting soil and acclimatized to outdoor conditions.

  10. Plant peroxisomes are degraded by starvation-induced and constitutive autophagy in tobacco BY-2 suspension-cultured cells.

    Science.gov (United States)

    Voitsekhovskaja, Olga V; Schiermeyer, Andreas; Reumann, Sigrun

    2014-01-01

    Very recently, autophagy has been recognized as an important degradation pathway for quality control of peroxisomes in Arabidopsis plants. To further characterize the role of autophagy in plant peroxisome degradation, we generated stable transgenic suspension-cultured cell lines of heterotrophic Nicotiana tabacum L. cv. Bright Yellow 2 expressing a peroxisome-targeted version of enhanced yellow fluorescent protein. Indeed, this cell line model system proved advantageous for detailed cytological analyses of autophagy stages and for quantification of cellular peroxisome pools under different culturing conditions and upon inhibitor applications. Complementary biochemical, cytological, and pharmacological analyses provided convincing evidence for peroxisome degradation by bulk autophagy during carbohydrate starvation. This degradation was slowed down by the inhibitor of autophagy, 3-methyladenine (3-MA), but the 3-MA effect ceased at advanced stages of starvation, indicating that another degradation mechanism for peroxisomes might have taken over. 3-MA also caused an increase particularly in peroxisomal proteins and cellular peroxisome numbers when applied under nutrient-rich conditions in the logarithmic growth phase, suggesting a high turnover rate for peroxisomes by basal autophagy under non-stress conditions. Together, our data demonstrate that a great fraction of the peroxisome pool is subject to extensive autophagy-mediated turnover under both nutrient starvation and optimal growth conditions. Our analyses of the cellular pool size of peroxisomes provide a new tool for quantitative investigations of the role of plant peroxisomes in reactive oxygen species metabolism.

  11. Metabolism of ibuprofen in higher plants: A model Arabidopsis thaliana cell suspension culture system

    Czech Academy of Sciences Publication Activity Database

    Maršík, Petr; Šíša, Miroslav; Lacina, O.; Moťková, Kateřina; Langhansová, Lenka; Rezek, Jan; Vaněk, Tomáš

    2017-01-01

    Roč. 220, JAN (2017), s. 383-392 ISSN 0269-7491 R&D Projects: GA ČR(CZ) GA14-22593S Grant - others:European Regional Development Fund(XE) CZ.2.16/3.1.00/24014 Institutional support: RVO:61389030 Keywords : Arabidopsis thaliana * Ibuprofen * Metabolism * Plant cells * Sequestration Subject RIV: CE - Biochemistry OBOR OECD: Plant sciences, botany Impact factor: 5.099, year: 2016

  12. Zinc tolerance and accumulation in stable cell suspension cultures and in vitro regenerated plants of the emerging model plant Arabidopsis halleri (Brassicaceae).

    Science.gov (United States)

    Vera-Estrella, Rosario; Miranda-Vergara, Maria Cristina; Barkla, Bronwyn J

    2009-03-01

    Arabidopsis halleri is increasingly employed as a model plant for studying heavy metal hyperaccumulation. With the aim of providing valuable tools for studies on cellular physiology and molecular biology of metal tolerance and transport, this study reports the development of successful and highly efficient methods for the in vitro regeneration of A. halleri plants and production of stable cell suspension lines. Plants were regenerated from leaf explants of A. halleri via a three-step procedure: callus induction, somatic embryogenesis and shoot development. Efficiency of callus proliferation and regeneration depended on the initial callus induction media and was optimal in the presence of 1 mg L(-1) 2,4-dichlorophenoxyacetic acid, and 0.05 mg L(-1) benzylaminopurine. Subsequent shoot and root regeneration from callus initiated under these conditions reached levels of 100% efficiency. High friability of the callus supported the development of cell suspension cultures with minimal cellular aggregates. Characterization of regenerated plants and cell cultures determined that they maintained not only the zinc tolerance and requirement of the whole plant but also the ability to accumulate zinc; with plants accumulating up to 50.0 micromoles zinc g(-1) FW, and cell suspension cultures 30.9 micromoles zinc g(-1) DW. Together this work will provide the experimental basis for furthering our knowledge of A. halleri as a model heavy metal hyperaccumulating plant.

  13. First insights in the Eu(III) speciation in plant cell suspension cultures

    Energy Technology Data Exchange (ETDEWEB)

    Moll, Henry; Sachs, Susanne [Helmholtz-Zentrum Dresden-Rossendorf e.V., Dresden (Germany). Biogeochemistry

    2017-06-01

    More than 80 % of the initial Eu(III) amount was associated on Brassica napus cells after an incubation time of 24 h. The spectroscopic speciation of the cell-bound Eu(III) is characterized by an increased intensity of the {sup 7}F{sub 2} transition and prolonged luminescence lifetimes.

  14. First insights in the Eu(III) speciation in plant cell suspension cultures

    International Nuclear Information System (INIS)

    Moll, Henry; Sachs, Susanne

    2017-01-01

    More than 80 % of the initial Eu(III) amount was associated on Brassica napus cells after an incubation time of 24 h. The spectroscopic speciation of the cell-bound Eu(III) is characterized by an increased intensity of the "7F_2 transition and prolonged luminescence lifetimes.

  15. In vitro production of azadirachtin from cell suspension cultures of ...

    Indian Academy of Sciences (India)

    PRAKASH KUMAR G

    proven effective in the control of agricultural pests in an environmentally ..... Prakash G and Srivastava A K 2005 Statistical media optimization for cell growth and ... Juss. suspension cultures; Process Biochemistry 40 3795–3800. Prakash G ...

  16. Establishment of the callus and cell suspension culture of ...

    African Journals Online (AJOL)

    STORAGESEVER

    2009-10-05

    Oct 5, 2009 ... Full Length Research Paper. Establishment of the callus ... study provided an efficient way for E. angustifolia cell suspension culture to produce secondary metabolite. .... was also observed that in these treatments the stem.

  17. Establishment of sorghum cell suspension culture system for ...

    African Journals Online (AJOL)

    STORAGESEVER

    2008-03-18

    Mar 18, 2008 ... Additionally, sorghum cell suspension cultures have been initiated from the friable ... proteomics technologies. The field of proteomics is .... air dried at room temperature and resuspended in 2 ml of urea buffer [9 M urea, 2 M ...

  18. The Effect of Plant Growth Regulators and Different Explants on the Response of Tissue Culture and Cell Suspension Cultures of German Chamomile (Matricaria chamomilla L.

    Directory of Open Access Journals (Sweden)

    L. Koohi,

    2014-07-01

    Full Text Available German chamomile (Matricaria chamomilla L. is one of the most important medicinal plants that its essential oils used in different medicinal industries. In this study which was carried out in 2013 growing season at the Faculty of Agricultural Sciences of the University of Mohaghegh Ardabili, the in vitro response of leaf and hypocotyl explants of German Chamomile in B5 medium supplemented with different levels of plant growth regulators including 2,4-D, naphthalene acetic acid (NAA, kinetin and 6-benzylaminopurine (BAP were investigated in a factorial experiment based on completely randomized design (CRD.In addition, cell suspension cultures were established and characterized. Hypocotyl and leaf explants exhibited cell proliferation and produced callus within 1-2 weeks. The highest fresh weight of the callus (264.1 mg was produced by leaf explants in the medium supplemented with 0.5 mg/l 2,4-D and 1 mg/l BAP. However, the leaf explants cultured on medium containing 1.5 mg/l 2,4-D showed the lowest cell proliferation and callus yield (40.42 mg. The highest percentage of root induction from leaf explants (58.73% was observed on the medium containing 4 mg/l 2,4-D and 1 mg/l Kin, and from hypocotyl explants (48.61% was observed on medium supplemented with 1.5 mg/l NAA. The 42.22% of calli derived from hypocotyl explants on B5 medium supplemented with 4 mg/l NAA and 3 mg/l BAP, were friable. Cell suspension cultures of German chamomile were established by transferring of hypocotyl-derived friable calli into the MS medium supplemented with 1.5 mg/l 2,4-D and 1 mg/l kinetin. The growth curve of cell proliferations started 4 days after culture and continued to grow until day 13th, where the cells entered stationary phase.

  19. Establishment and characterization of American elm cell suspension cultures

    Science.gov (United States)

    Steven M. Eshita; Joseph C. Kamalay; Vicki M. Gingas; Daniel A. Yaussy

    2000-01-01

    Cell suspension cultures of Dutch elm disease (DED)-tolerant and DED-susceptible American elms clones have been established and characterized as prerequisites for contrasts of cellular responses to pathogen-derived elicitors. Characteristics of cultured elm cell growth were monitored by A700 and media conductivity. Combined cell growth data for all experiments within a...

  20. Establishment of the callus and cell suspension culture of ...

    African Journals Online (AJOL)

    The objective of this work was the optimization of the conditions of callus and cell suspension culture of Elaeagnus angustifolia for the production of condensed tannins. The effects of different conditions on the callus growth and the production of condensed tannins were researched. The leaf tissue part of E. angustifolia was ...

  1. Flavonoid Production, Growth and Differentiation of Stelechocarpus burahol (Bl.) Hook. F. and Th. Cell Suspension Culture.

    Science.gov (United States)

    Aini Habibah, Noor; Moeljopawiro, Sukarti; Dewi, Kumala; Indrianto, Ari

    2017-01-01

    Stelechocarpus burahol is a plant containing flavonoid compounds that have the potential for use as an antihyperuricemic for gout medication. This study was performed to assess flavonoid production, growth and cell differentiation of S. burahol in cell suspension culture. Mesocarp was planted in Murashige and Skoog (MS) medium supplemented with 7.5 mg L-1 picloram for the induction of callus. Non-embryonic callus obtained was used in the formation of cell suspension cultures. Growth of cells was determined by fresh and dry weights. During the culturing, the fresh weight, dry weight and flavonoid content were determined as a result of culture status. The growth of the S. burahol cell suspension was slow, the stationary phase occurred at 30 days. The production of flavonoids was not in line with the growth of cells and the maximum production occurred on the 15th day of the log phase. The globular-shaped cells dominated the cell suspension culture at all ages. Fluorescein diacetate (FDA) staining of cells derived from cell cultures aged for 36 days showed that some cells were still viable. The results show that flavonoid production, growth and cell differentiation of a S. burahol cell suspension culture differed according to the culture age.

  2. Determination of specific growth stages of plant cell suspension cultures by monitoring conductivity changes in the medium.

    Science.gov (United States)

    Hahlbrock, K; Ebel, J; Oaks, A; Auden, J; Liersch, M

    1974-03-01

    Conductivity changes in the medium of cultured soybean (Glycine max L.) cells were shown to be strictly correlated with nitrate uptake and growth of the cultures. A continuous record of the conductivity was used as a simple and reliable method of determining specific growth stages and concomitant peaks in the activities of nitrate reductase and phenylalanine ammonia-lyase.

  3. ( Linum usitatissimum L. cv. Modran cell suspension culture

    Directory of Open Access Journals (Sweden)

    Aleksandra Seta-Koselska

    2018-01-01

    Full Text Available Flax ( Linum usitatissimum L. is an ancient crop that is widely cultivated as a source of oil, fiber, and bioactive compounds. Flax fiber is traditionally used in textile industry, linseed oil is processed for industrial oils, paints, varnishes and bio-petroleum. Flaxseeds are also rich in α-linolenic acid and phytochemicals such as lignans. In addition to the commercial aspects, this species has been used widely and readily in biotechnological, developmental, and plant-pathogen interaction studies. Differences in the levels of endogenous hormones in various cultivars of flax significantly affected the intensity of callogenesis and determined the type and concentration of growth regulators necessary for callus production. The aim of our investigation was to optimize the culture conditions for callus formation and cell proliferation in liquid medium of the Polish cultivar of fiber flax – Modran. In the first step, 4 combinations of phytohormones in the medium were tested to obtain established callus tissue suitable for initiation of suspension culture. Next, we investigated the effect of chosen plant growth regulators on cell divisions, fresh and dry weight, and dispersal of callus cells in liquid medium. Fast growing and friable callus was obtained in a modified MS medium supplemented with 0.5 mg/l BAP and 0.1 mg/l NAA. We determined that for the initiation of cell suspension supplementation with 0.5 mg/l BAP and 0.5 mg/l NAA is optimal. The results obtained indicated that high concentration of cytokinin (BAP in liquid medium limited cell proliferation and decreased biomass formation.

  4. Enhancement of Shikonin Production in Suspension Cultures of Lithospermum erythrorhizon Cells by Gamma-irradiation

    International Nuclear Information System (INIS)

    Baek, Myung Hwa; Chung, Byung Yeoup; Kim, Jae Sung; An, Beyoung Chul; Lee, Young Bok

    2005-01-01

    The shikonin and several derivatives produced by the roots of Boraginacae family plants are purple compounds that have been used in several parts of the World as antimicrobial and antitumor agents in human pharmaceuticals. Shikonin has been reported as the most successful specimen of the mass production of plant secondary metabolites by cell suspension culture. Numerous studies have elucidated the regulation of production of these compounds in cell suspension cultures. It has known that ultrasonic and gamma irradiation can enhance the production of secondary metabolites. Thus, in present study, we investigate the effects of gamma-irradiation on the shikonin production and the key enzymes in the shikonin biosynthetic pathway of L. erythrorhizon cells

  5. Growth and Plating of Cell Suspension Cultures of Datura Innoxia

    DEFF Research Database (Denmark)

    Engvild, Kjeld Christensen

    1974-01-01

    Suspension cultures of Datura innoxia Mill, were successfully grown on a modified Murashige and Skoog medium with 2,4–D, NAA or BAP as growth substances, provided the micronutrient levels were reduced to 1/10. Normal amounts of micronutrients were toxic. Attempts to identify the toxic elements did...... not succeed. Cultures grew exponentially on a shaker at 27°C in the light. Their doubling times varied from 1.1 days on 2,4–D (10–6M) or NAA (10−5M)+ 1 g/1 casein hydrolysate to 2.7 days on BAP (3 × 10−7M) and 5.1 days on supraoptimal levels of 2,4-D (10−5M). Cultures grew on NH4+-N alone (from ammonium...... malate) or on NO3−-N alone. Dry weight yield was proportional to the amount of nitrate-N added (47 mg/mg N). Filtered suspension cultures containing single cells (plating cultures) could be grown in agar in petri dishes when NAA or 2,4-D were used as growth substances. Cells grew at densities above 500...

  6. Regio-selective deglycosylation of icariin by cell suspension cultures of Glycyrrhiza uralensis and Morus alba.

    Science.gov (United States)

    Zhang, De-Wu; Tao, Xiao-Yu; Chen, Ri-Dao; Yu, Li-Yan; Dai, Jun-Gui

    2015-01-01

    Biotransformations of icariin (1) by cell suspension cultures of Glycyrrhiza uralensis and Morus alba yielded two new metabolites, icaruralins A and B (2 and 3), and one known metabolite, baohuoside I (4). Their structures were determined on the basis of extensive spectroscopic analysis. This is the first report that the cell suspension cultures of G. uralensis and M. alba possess deglycosylation functionality.

  7. Enhanced Production of Anthraquinones and Phenolic Compounds and Biological Activities in the Cell Suspension Cultures of Polygonum multiflorum

    Directory of Open Access Journals (Sweden)

    Muthu Thiruvengadam

    2016-11-01

    Full Text Available Anthraquinones (AQs and phenolic compounds are important phytochemicals that are biosynthesized in cell suspension cultures of Polygonum multiflorum. We wanted to optimize the effects of plant growth regulators (PGRs, media, sucrose, l-glutamine, jasmonic acid (JA, and salicylic acid (SA for the production of phytochemicals and biomass accumulation in a cell suspension culture of P. multiflorum. The medium containing Murashige and Skoog (MS salts and 4% sucrose supplemented with 1 mg/L 2,4-dichlorophenoxyacetic acid, 0.5 mg/L thidiazuron, and 100 µM l-glutamine at 28 days of cell suspension culture was suitable for biomass accumulation and AQ production. Maximum biomass accumulation (12.5 and 12.35 g fresh mass (FM; 3 and 2.93 g dry mass (DM and AQ production (emodin 295.20 and 282 mg/g DM; physcion 421.55 and 410.25 mg/g DM were observed using 100 µM JA and SA, respectively. JA- and SA-elicited cell cultures showed several-fold higher biomass accumulation and AQ production than the control cell cultures. Furthermore, the cell suspension cultures effectively produced 23 phenolic compounds, such as flavonols and hydroxycinnamic and hydroxybenzoic acid derivatives. PGR-, JA-, and SA-elicited cell cultures produced a higher amount of AQs and phenolic compounds. Because of these metabolic changes, the antioxidant, antimicrobial, and anticancer activities were high in the PGR-, JA-, and SA-elicited cell cultures. The results showed that the elicitors (JA and SA induced the enhancement of biomass accumulation and phytochemical (AQs and phenolic compounds production as well as biological activities in the cell suspension cultures of P. multiflorum. This optimized protocol can be developed for large-scale biomass accumulation and production of phytochemicals (AQs and phenolic compounds from cell suspension cultures, and the phytochemicals can be used for various biological activities.

  8. Enhanced Production of Anthraquinones and Phenolic Compounds and Biological Activities in the Cell Suspension Cultures of Polygonum multiflorum

    Science.gov (United States)

    Thiruvengadam, Muthu; Rekha, Kaliyaperumal; Rajakumar, Govindasamy; Lee, Taek-Jun; Kim, Seung-Hyun; Chung, Ill-Min

    2016-01-01

    Anthraquinones (AQs) and phenolic compounds are important phytochemicals that are biosynthesized in cell suspension cultures of Polygonum multiflorum. We wanted to optimize the effects of plant growth regulators (PGRs), media, sucrose, l-glutamine, jasmonic acid (JA), and salicylic acid (SA) for the production of phytochemicals and biomass accumulation in a cell suspension culture of P. multiflorum. The medium containing Murashige and Skoog (MS) salts and 4% sucrose supplemented with 1 mg/L 2,4-dichlorophenoxyacetic acid, 0.5 mg/L thidiazuron, and 100 µM l-glutamine at 28 days of cell suspension culture was suitable for biomass accumulation and AQ production. Maximum biomass accumulation (12.5 and 12.35 g fresh mass (FM); 3 and 2.93 g dry mass (DM)) and AQ production (emodin 295.20 and 282 mg/g DM; physcion 421.55 and 410.25 mg/g DM) were observed using 100 µM JA and SA, respectively. JA- and SA-elicited cell cultures showed several-fold higher biomass accumulation and AQ production than the control cell cultures. Furthermore, the cell suspension cultures effectively produced 23 phenolic compounds, such as flavonols and hydroxycinnamic and hydroxybenzoic acid derivatives. PGR-, JA-, and SA-elicited cell cultures produced a higher amount of AQs and phenolic compounds. Because of these metabolic changes, the antioxidant, antimicrobial, and anticancer activities were high in the PGR-, JA-, and SA-elicited cell cultures. The results showed that the elicitors (JA and SA) induced the enhancement of biomass accumulation and phytochemical (AQs and phenolic compounds) production as well as biological activities in the cell suspension cultures of P. multiflorum. This optimized protocol can be developed for large-scale biomass accumulation and production of phytochemicals (AQs and phenolic compounds) from cell suspension cultures, and the phytochemicals can be used for various biological activities. PMID:27854330

  9. Effect of Magnetic Nanoparticles on Tobacco BY-2 Cell Suspension Culture

    Science.gov (United States)

    Krystofova, Olga; Sochor, Jiri; Zitka, Ondrej; Babula, Petr; Kudrle, Vit; Adam, Vojtech; Kizek, Rene

    2012-01-01

    Nanomaterials are structures whose exceptionality is based on their large surface, which is closely connected with reactivity and modification possibilities. Due to these properties nanomaterials are used in textile industry (antibacterial textiles with silver nanoparticles), electronics (high-resolution imaging, logical circuits on the molecular level) and medicine. Medicine represents one of the most important fields of application of nanomaterials. They are investigated in connection with targeted therapy (infectious diseases, malignant diseases) or imaging (contrast agents). Nanomaterials including nanoparticles have a great application potential in the targeted transport of pharmaceuticals. However, there are some negative properties of nanoparticles, which must be carefully solved, as hydrophobic properties leading to instability in aqueous environment, and especially their possible toxicity. Data about toxicity of nanomaterials are still scarce. Due to this fact, in this work we focused on studying of the effect of magnetic nanoparticles (NPs) and modified magnetic nanoparticles (MNPs) on tobacco BY-2 plant cell suspension culture. We aimed at examining the effect of NPs and MNPs on growth, proteosynthesis—total protein content, thiols—reduced (GSH) and oxidized (GSSG) glutathione, phytochelatins PC2-5, glutathione S-transferase (GST) activity and antioxidant activity of BY-2 cells. Whereas the effect of NPs and MNPs on growth of cell suspension culture was only moderate, significant changes were detected in all other biochemical parameters. Significant changes in protein content, phytochelatins levels and GST activity were observed in BY-2 cells treated with MNPs nanoparticles treatment. Changes were also clearly evident in the case of application of NPs. Our results demonstrate the ability of MNPs to negatively affect metabolism and induce biosynthesis of protective compounds in a plant cell model represented by BY-2 cell suspension culture. The

  10. Induction of phytic acid synthesis by abscisic acid in suspension-cultured cells of rice.

    Science.gov (United States)

    Matsuno, Koya; Fujimura, Tatsuhito

    2014-03-01

    A pathway of phytic acid (PA) synthesis in plants has been revealed via investigations of low phytic acid mutants. However, the regulation of this pathway is not well understood because it is difficult to control the environments of cells in the seeds, where PA is mainly synthesized. We modified a rice suspension culture system in order to study the regulation of PA synthesis. Rice cells cultured with abscisic acid (ABA) accumulate PA at higher levels than cells cultured without ABA, and PA accumulation levels increase with ABA concentration. On the other hand, higher concentrations of sucrose or inorganic phosphorus do not affect PA accumulation. Mutations in the genes RINO1, OsMIK, OsIPK1 and OsLPA1 have each been reported to confer low phytic acid phenotypes in seeds. Each of these genes is upregulated in cells cultured with ABA. OsITPK4 and OsITPK6 are upregulated in cells cultured with ABA and in developing seeds. These results suggest that the regulation of PA synthesis is similar between developing seeds and cells in this suspension culture system. This system will be a powerful tool for elucidating the regulation of PA synthesis. Copyright © 2014 Elsevier Ireland Ltd. All rights reserved.

  11. Suspension culture combined with chemotherapeutic agents for sorting of breast cancer stem cells

    International Nuclear Information System (INIS)

    Li, Hai-zhi; Yi, Tong-bo; Wu, Zheng-yan

    2008-01-01

    Cancer stem cell (CSC) hypothesis has not been well demonstrated by the lack of the most convincing evidence concerning a single cell capable of giving rise to a tumor. The scarcity in quantity and improper approaches for isolation and purification of CSCs have become the major obstacles for great development in CSCs. Here we adopted suspension culture combined with anticancer regimens as a strategy for screening breast cancer stem cells (BrCSCs). BrCSCs could survive and be highly enriched in non-adherent suspension culture while chemotherapeutic agents could destroy most rapidly dividing cancer cells and spare relatively quiescent BrCSCs. TM40D murine breast cancer cells were cultured in serum-free medium. The expression of CD44 + CD24 - was measured by flow cytometry. Cells of passage 10 were treated in combination with anticancer agents pacilitaxel and epirubicin at different peak plasma concentrations for 24 hours, and then maintained under suspension culture. The rate of apoptosis was examined by flow cytometry with Annexin-V fluorescein isothiocyanate (FITC)/propidium iodide (PI) double staining method. Selected cells in different amounts were injected subcutaneously into BALB/C mice to observe tumor formation. Cells of passage 10 in suspension culture had the highest percentage of CD44 + CD24 - (about 77 percent). A single tumor cell in 0.35 PPC could generate tumors in 3 of 20 BALB/C mice. Suspension culture combined with anticancer regimens provides an effective means of isolating, culturing and purifying BrCSCs

  12. Development of a scalable suspension culture for cardiac differentiation from human pluripotent stem cells

    Directory of Open Access Journals (Sweden)

    Vincent C. Chen

    2015-09-01

    Full Text Available To meet the need of a large quantity of hPSC-derived cardiomyocytes (CM for pre-clinical and clinical studies, a robust and scalable differentiation system for CM production is essential. With a human pluripotent stem cells (hPSC aggregate suspension culture system we established previously, we developed a matrix-free, scalable, and GMP-compliant process for directing hPSC differentiation to CM in suspension culture by modulating Wnt pathways with small molecules. By optimizing critical process parameters including: cell aggregate size, small molecule concentrations, induction timing, and agitation rate, we were able to consistently differentiate hPSCs to >90% CM purity with an average yield of 1.5 to 2 × 109 CM/L at scales up to 1 L spinner flasks. CM generated from the suspension culture displayed typical genetic, morphological, and electrophysiological cardiac cell characteristics. This suspension culture system allows seamless transition from hPSC expansion to CM differentiation in a continuous suspension culture. It not only provides a cost and labor effective scalable process for large scale CM production, but also provides a bioreactor prototype for automation of cell manufacturing, which will accelerate the advance of hPSC research towards therapeutic applications.

  13. An efficient method for the establishment of cell suspension cultures in potato (Solanum tuberosum L.)

    International Nuclear Information System (INIS)

    Sajid, Z.A.

    2016-01-01

    Cell suspension cultures offers an In vitro system that can be used as a tool for various studies involving mutant selection, mass propagation, protoplast isolation, gene transfer and selection of cell-lines which are resistant to various biotic or abiotic stresses. Research work on the development of cell suspension cultures was carried out to establish the most efficient method in Potato (cv. Desiree). Healthy, well-proliferating tissues from different types of callus cultures (compact, friable, embryogenic or non-embryogenic) were inoculated on various media combinations, i.e., MS, MS2 or AA liquid medium containing 18.09 micro M 2, 4-D. A fixed quantity (0.5-1.0 g) of callus tissue from 60-day-old callus cultures was transferred to 10-25 ml of liquid medium in 100 ml Erlenmeyer flask. Cultures were placed on an orbital shaker and agitated at different speeds (75, 100 or 125 rpm) under 16-h photoperiod at 25 ± 2 degree C. Medium was changed after every 3 days and fractionated tissue was filtered after every 6 days through sterile mesh (100-800 micro m) to develop a cell-line by transferring resulting suspension to fresh medium under the same conditions. Results indicated that eight-week-old translucent, friable, off-white callus cultures were an excellent starting material for the initiation of homogeneous cell suspension cultures as compared to other tested sources. Of the three tested media (MS, MS2 or AA medium containing 18.09 micro M 2, 4-D), MS2 was found to be a better medium for the initiation of cell suspension cultures. Cell suspension cultures, placed in 16-h photoperiod at 25 ± 2 degree C and agitated at 120 rpm using a gyratory shaker showed excellent results. Several other factors influencing quick establishment of cell suspension cultures in this cultivar are also discussed in this communication. (author)

  14. Efficient Secretion of Recombinant Proteins from Rice Suspension-Cultured Cells Modulated by the Choice of Signal Peptide.

    Science.gov (United States)

    Huang, Li-Fen; Tan, Chia-Chun; Yeh, Ju-Fang; Liu, Hsin-Yi; Liu, Yu-Kuo; Ho, Shin-Lon; Lu, Chung-An

    2015-01-01

    Plant-based expression systems have emerged as a competitive platform in the large-scale production of recombinant proteins. By adding a signal peptide, αAmy3sp, the desired recombinant proteins can be secreted outside transgenic rice cells, making them easy to harvest. In this work, to improve the secretion efficiency of recombinant proteins in rice expression systems, various signal peptides including αAmy3sp, CIN1sp, and 33KDsp have been fused to the N-terminus of green fluorescent protein (GFP) and introduced into rice cells to explore the efficiency of secretion of foreign proteins. 33KDsp had better efficiency than αAmy3sp and CIN1sp for the secretion of GFP from calli and suspension-cultured cells. 33KDsp was further applied for the secretion of mouse granulocyte-macrophage colony-stimulating factor (mGM-CSF) from transgenic rice suspension-cultured cells; approximately 76%-92% of total rice-derived mGM-CSF (rmGM-CSF) was detected in the culture medium. The rmGM-CSF was bioactive and could stimulate the proliferation of a murine myeloblastic leukemia cell line, NSF-60. The extracellular yield of rmGM-CSF reached 31.7 mg/L. Our study indicates that 33KDsp is better at promoting the secretion of recombinant proteins in rice suspension-cultured cell systems than the commonly used αAmy3sp.

  15. Structure and organ specificity of an anionic peroxidase from Arabidopsis thaliana cell suspension culture

    DEFF Research Database (Denmark)

    Ostergaard, L; Abelskov, A K; Mattsson, O

    1996-01-01

    The predominant peroxidase (pI 3.5) (E.C. 1.11.1.7) of an Arabidopsis thaliana cell suspension culture was purified and partially sequenced. Oligonucleotides were designed and a specific probe was obtained. A cDNA clone was isolated from an Arabidopsis cell suspension cDNA library and completely ...

  16. Isolation of plasmodesmata from Arabidopsis suspension culture cells.

    Science.gov (United States)

    Grison, Magali S; Fernandez-Calvino, Lourdes; Mongrand, Sébastien; Bayer, Emmanuelle M F

    2015-01-01

    Due to their position firmly anchored within the plant cell wall, plasmodesmata (PD) are notoriously difficult to isolate from plant tissue. Yet, getting access to isolated PD represents the most straightforward strategy for the identification of their molecular components. Proteomic and lipidomic analyses of such PD fractions have provided and will continue to provide critical information on the functional and structural elements that define these membranous nano-pores. Here, we describe a two-step simple purification procedure that allows isolation of pure PD-derived membranes from Arabidopsis suspension cells. The first step of this procedure consists in isolating cell wall fragments containing intact PD while free of contamination from other cellular compartments. The second step relies on an enzymatic degradation of the wall matrix and the subsequent release of "free" PD. Isolated PD membranes provide a suitable starting material for the analysis of PD-associated proteins and lipids.

  17. Biochemical precursor effects on the fatty acid production in cell suspension cultures of Theobroma cacao L.

    Science.gov (United States)

    Parra, O; Gallego, A M; Urrea, A; Rojas, L F; Correa, C; Atehortúa, L

    2017-02-01

    Cocoa butter (CB) is composed of 96% palmitic, stearic, oleic, linoleic and linolenic fatty acids that are responsible for the hardness, texture and fusion properties of chocolate. Through in vitro plant cell culture it is possible to modify CB lipid profiles and to study the fatty acid biosynthesis pathway on a subcellular level, evaluating fundamental aspects to enhance in vitro fatty acid production in a specific and controlled way. In this research, culture media was supplemented with acetate, biotin, pyruvate, bicarbonate and glycerol at three different concentrations and the effects on the biomass production (g/L), cell viability, and fatty acids profile and production was evaluated in in vitro cell suspensions culture. It was found that biotin stimulated fatty acid synthesis without altering cell viability and cell growth. It was also evident a change in the lipid profile of cell suspensions, increasing middle and long chain fatty acids proportion, which are unusual to those reported in seeds; thus implying that it is possible to modify lipid profiles according to the treatment used. According to the results of sucrose gradients and enzyme assays performed, it is proposed that cacao cells probably use the pentose phosphate pathway, mitochondria being the key organelle in the carbon flux for the synthesis of reductant power and fatty acid precursors. Copyright © 2016 Elsevier Masson SAS. All rights reserved.

  18. Assessment of cultivation factors that affect biomass and geraniol production in transgenic tobacco cell suspension cultures.

    Directory of Open Access Journals (Sweden)

    Nikolay Vasilev

    Full Text Available A large-scale statistical experimental design was used to determine essential cultivation parameters that affect biomass accumulation and geraniol production in transgenic tobacco (Nicotiana tabacum cv. Samsun NN cell suspension cultures. The carbohydrate source played a major role in determining the geraniol yield and factors such as filling volume, inoculum size and light were less important. Sucrose, filling volume and inoculum size had a positive effect on geraniol yield by boosting growth of plant cell cultures whereas illumination of the cultures stimulated the geraniol biosynthesis. We also found that the carbohydrates sucrose and mannitol showed polarizing effects on biomass and geraniol accumulation. Factors such as shaking frequency, the presence of conditioned medium and solubilizers had minor influence on both plant cell growth and geraniol content. When cells were cultivated under the screened conditions for all the investigated factors, the cultures produced ∼ 5.2 mg/l geraniol after 12 days of cultivation in shaking flasks which is comparable to the yield obtained in microbial expression systems. Our data suggest that industrial experimental designs based on orthogonal arrays are suitable for the selection of initial cultivation parameters prior to the essential medium optimization steps. Such designs are particularly beneficial in the early optimization steps when many factors must be screened, increasing the statistical power of the experiments without increasing the demand on time and resources.

  19. Suspension culture of pluripotent stem cells: effect of shear on stem cell fate.

    Science.gov (United States)

    Keller, Kevin C; Rodrigues, Beatriz; zur Nieden, Nicole I

    2014-01-01

    Despite significant promise, the routine usage of suspension cell culture to manufacture stem cell-derived differentiated cells has progressed slowly. Suspension culture is an innovative way of either expanding or differentiating cells and sometimes both are combined into a single bioprocess. Its advantages over static 2D culturing include a homogeneous and controllable culture environment and producing a large quantity of cells in a fraction of time. This feature makes suspension cell culture ideal for use in stem cell research and eventually ideal in the large-scale production of differentiated cells for regenerative medicine. Because of their tremendous differentiation capacities and unlimited growth properties, pluripotent stem cells (PSCs) in particular are considered potential sources for future cell-replacement therapies. Currently, expansion of PSCs is accomplished in 2D, which only permits a limited amount of cell growth per culture flask before cells need to be passaged. However, before stem cells can be applied clinically, several aspects of their expansion, such as directed growth, but also differentiation, need to be better controlled. This review will summarize recent advantages in suspension culture of PSCs, while at the same time highlighting current challenges.

  20. Neuropharmacological and neuroprotective activities of some metabolites produced by cell suspension culture of Waltheria americana Linn.

    Science.gov (United States)

    Mundo, Jorge; Villeda-Hernández, Juana; Herrera-Ruiz, Maribel; Gutiérrez, María Del Carmen; Arellano-García, Jesús; León-Rivera, Ismael; Perea-Arango, Irene

    2017-10-01

    Waltheria americana is a plant used in Mexican traditional medicine to treat some nervous system disorders. The aims of the present study were to isolate and determine the neuropharmacological and neurprotective activities of metabolites produced by a cell suspension culture of Waltheria americana. Submerged cultivation of W. americana cells provided biomass. A methanol-soluble extract (WAsc) was obtained from biomass. WAsc was fractionated yielding the chromatographic fractions 4WAsc-H 2 O and WAsc-CH 2 Cl 2 . For the determination of anticonvulsant activity in vivo, seizures were induced in mice by pentylenetetrazol (PTZ). Neuropharmacological activities (release of gamma amino butyric acid (GABA) and neuroprotection) of chromatographic fractions were determined by in vitro histological analysis of brain sections of mice post mortem. Fraction 4WAsc-H 2 O (containing saccharides) did not produce neuronal damage, neurodegeneration, interstitial tissue edema, astrocytic activation, nor cell death. Pretreatment of animals with 4WAsc-H 2 O and WAsc-CH 2 Cl 2 from W. americana cell suspensions induced an increase in: GABA release, seizure latency, survival time, neuroprotection, and a decrease in the degree of severity of tonic/tonic-clonic convulsions, preventing PTZ-induced death of up to 100% of animals of study. Bioactive compounds produced in suspension cell culture of W. americana produce neuroprotective and neuropharmacological activities associated with the GABAergic neurotransmission system. Copyright © 2017 Elsevier Masson SAS. All rights reserved.

  1. Rosmarinic acid and antioxidant enzyme activities in Lavandula vera MM cell suspension culture: a comparative study.

    Science.gov (United States)

    Georgiev, Milen; Abrashev, Radoslav; Krumova, Ekaterina; Demirevska, Klimentina; Ilieva, Mladenka; Angelova, Maria

    2009-11-01

    The growth and intracellular protein content of lavender (Lavandula vera MM) cell suspension culture was followed along with some antioxidant defense system members-non-enzymatic (rosmarinic acid) and enzymatic [superoxide dismutase (EC 1.15.1.1) and catalase (EC 1.11.1.6)]. It was found that the media content and the cultivation mode strongly influenced the production of plant defense compounds as well as the ratio between non-enzymatic and enzymatic ones. The bioreactor culture contains about two times more rosmarinic acid, superoxide dismutase, and catalase compared to the shake-flask cultivation. These findings are discussed with respect to the relative stress levels and plant antioxidant orchestra system. It was concluded that investigated defense system components (enzymatic and non-enzymatic) were closely associated in a complex balance. The three isoenzyme forms of SOD (Cu/ZnSOD, FeSOD, and MnSOD) in the cells of Lavandula vera were revealed by polyacrylamide gel electrophoresis analysis, and the FeSOD isoform exhibited highest activity.

  2. Effects of Selected Physicochemical Parameters on Zerumbone Production of Zingiber zerumbet Smith Cell Suspension Culture.

    Science.gov (United States)

    Jalil, Mahanom; Annuar, Mohamad Suffian Mohamad; Tan, Boon Chin; Khalid, Norzulaani

    2015-01-01

    Zingiber zerumbet Smith is an important herb that contains bioactive phytomedicinal compound, zerumbone. To enhance cell growth and production of this useful compound, we investigated the growth conditions of cell suspension culture. Embryogenic callus generated from shoot bud was used to initiate cell suspension culture. The highest specific growth rate of cells was recorded when it was cultured in liquid Murashige and Skoog basal medium containing 3% sucrose with pH 5.7 and incubated under continuous shaking condition of 70 rpm for 16 h light and 8 h dark cycle at 24°C. Our results also revealed that the type of carbohydrate substrate, light regime, agitation speed, and incubation temperature could affect the production of zerumbone. Although the zerumbone produced in this study was not abundant compared to rhizome of Z. zerumbet, the possibility of producing zerumbone during early stage could serve as a model for subsequent improvement.

  3. Effects of Selected Physicochemical Parameters on Zerumbone Production of Zingiber zerumbet Smith Cell Suspension Culture

    Directory of Open Access Journals (Sweden)

    Mahanom Jalil

    2015-01-01

    Full Text Available Zingiber zerumbet Smith is an important herb that contains bioactive phytomedicinal compound, zerumbone. To enhance cell growth and production of this useful compound, we investigated the growth conditions of cell suspension culture. Embryogenic callus generated from shoot bud was used to initiate cell suspension culture. The highest specific growth rate of cells was recorded when it was cultured in liquid Murashige and Skoog basal medium containing 3% sucrose with pH 5.7 and incubated under continuous shaking condition of 70 rpm for 16 h light and 8 h dark cycle at 24°C. Our results also revealed that the type of carbohydrate substrate, light regime, agitation speed, and incubation temperature could affect the production of zerumbone. Although the zerumbone produced in this study was not abundant compared to rhizome of Z. zerumbet, the possibility of producing zerumbone during early stage could serve as a model for subsequent improvement.

  4. Xyloglucan biosynthesis by Golgi membranes from suspension-cultured sycamore (Acer pseudoplatanus) cells

    International Nuclear Information System (INIS)

    White, A.R.; Xin, Yi

    1990-01-01

    Xyloglucan is a major hemicellulose polysaccharide in plant cell walls. Biosynthesis of such cell wall polysaccharides is closely linked to the process of plant cell growth and development. Xyloglucan polysaccharides consist of a β-1,4 glucan backbone synthesized by xyloglucan synthase and sidechains of xylose, galactose, and fucose added by other transferase enzymes. Most plant Golgi and plasma membranes also contain glucan synthases I ampersand II, which make β-1,4 and β-1,3 glucans, respectively. All of these enzymes have very similar activities. Cell walls on suspension-cultured cells from Acer pseudoplatanus (sycamore maple) were enzymatically softened prior to cell disruption by passing through a 30 μm nylon screen. Cell membranes from homogenates were separated by ultracentrifugation on top-loaded or flotation sucrose density gradients. Samples were collected by gradient fractionation and assayed for membrane markers and xyloglucan and glucan synthase activities. Standard marker assays (cyt. c reductase for eR, IDPase ampersand UDPase for Golgi, and eosin 5'-malelmide binding for plasma membrane) showed partial separation of these three membrane types. Golgi and plasma membrane markers overlapped in most gradients. Incorporation of 14 C-labeled sugars from UDP-glucose and UDP-xylose was used to detect xyloglucan synthase, glucan synthases I ampersand II, and xylosyl transferase in Golgi membrane fractions. These activities overlapped, although distinct peaks of xyloglucan synthase and xylosyl transferase were found. Ca ++ had a stimulatory effect on glucan synthases I ampersand II, while Mn ++ had an inhibitory effect on glucan synthase I in the presence of Ca ++ . The similarity of these various synthase activities demonstrates the need for careful structural characterization of newly synthesized polysaccharides

  5. Affinity Purification and Characterization of Functional Tubulin from Cell Suspension Cultures of Arabidopsis and Tobacco1

    Science.gov (United States)

    Fujita, Satoshi; Uchimura, Seiichi; Noguchi, Masahiro; Demura, Taku

    2016-01-01

    Microtubules assemble into several distinct arrays that play important roles in cell division and cell morphogenesis. To decipher the mechanisms that regulate the dynamics and organization of this versatile cytoskeletal component, it is essential to establish in vitro assays that use functional tubulin. Although plant tubulin has been purified previously from protoplasts by reversible taxol-induced polymerization, a simple and efficient purification method has yet to be developed. Here, we used a Tumor Overexpressed Gene (TOG) column, in which the tubulin-binding domains of a yeast (Saccharomyces cerevisiae) TOG homolog are immobilized on resin, to isolate functional plant tubulin. We found that several hundred micrograms of pure tubulin can readily be purified from cell suspension cultures of tobacco (Nicotiana tabacum) and Arabidopsis (Arabidopsis thaliana). The tubulin purified by the TOG column showed high assembly competence, partly because of low levels of polymerization-inhibitory phosphorylation of α-tubulin. Compared with porcine brain tubulin, Arabidopsis tubulin is highly dynamic in vitro at both the plus and minus ends, exhibiting faster shrinkage rates and more frequent catastrophe events, and exhibits frequent spontaneous nucleation. Furthermore, our study shows that an internal histidine tag in α-tubulin can be used to prepare particular isotypes and specifically engineered versions of α-tubulin. In contrast to previous studies of plant tubulin, our mass spectrometry and immunoblot analyses failed to detect posttranslational modification of the isolated Arabidopsis tubulin or detected only low levels of posttranslational modification. This novel technology can be used to prepare assembly-competent, highly dynamic pure tubulin from plant cell cultures. PMID:26747285

  6. Adsorptive loss of secreted recombinant proteins in transgenic rice cell suspension cultures.

    Science.gov (United States)

    Kwon, Jun-Young; Lee, Kyoung-Hoon; Cheon, Su-Hwan; Ryu, Hyun-Nam; Kim, Sun Jin; Kim, Dong-Il

    2012-03-01

    Adsorptive loss of human cytotoxic T-lymphocyte antigen 4-immunoglobulin (hCTLA4Ig) in transgenic rice cell suspension cultures was investigated using glass flasks, plastic flasks, disposable vessels, and stainless steel vessels. When hCTLA4Ig was added to the glass flasks containing sterile AA medium, a rapid decrease in the concentration of hCTLA4Ig, independent on pH, was observed resulting in more than 90% of the protein loss within 1 h due to the surface adsorption. When the same experiments were performed on four different types of culture equipments mentioned above, the lowest adsorption level was observed in the plastic flasks and the highest level was observed in the glass flasks. The use of the plastic flasks retarded the adsorptive loss of hCTLA4Ig at the early stage of the protein production. There was a significant increase in the production of hCTLA4Ig when the flasks were coated with bovine serum albumin. However, the spike test of purified hCTLA4Ig at two different concentrations of 15 and 100 mg L(-1) in 500-mL spinner flasks confirmed that the amount of hCTLA4Ig adsorbed was dependent on the surface area of the flasks but not on the concentrations. In conclusion, although the protein adsorption affected the total amount of the protein yielded to some extent, it could be regarded as a minor factor in transgenic plant cell cultures with higher titer.

  7. High level of expression of recombinant human granulocyte-macrophage colony stimulating factor in transgenic rice cell suspension culture

    DEFF Research Database (Denmark)

    Shin, Yun-Ji; Hong, Shin-Young; Kwon, Tae-Ho

    2003-01-01

    Recombinant human granulocyte-macrophage colony stimulating factor (hGM-CSF) has been previously produced in tobacco cell suspension cultures. However, the amount of hGM-CSF accumulated in the culture medium dropped quickly from its maximum of 150 microg/L at 5 d after incubation. To overcome...... of recombinant hGM-CSF in transgenic rice cell suspension culture and protease activity of this culture medium was low compared to that of tobacco culture system....

  8. Signal transduction in artichoke [Cynara cardunculus L. subsp. scolymus (L.) Hayek] callus and cell suspension cultures under nutritional stress.

    Science.gov (United States)

    Lattanzio, Vincenzo; Caretto, Sofia; Linsalata, Vito; Colella, Giovanni; Mita, Giovanni

    2018-06-01

    Stimulated production of secondary phenolic metabolites and proline was studied by using cell cultures of artichoke [Cynara cardunculus L. subsp. scolymus (L.) Hayek] submitted to nutritional stress. Artichoke cell cultures accumulated phenolic secondary metabolites in a pattern similar to that seen in artichoke leaves and heads (capitula). This paper shows that both callus and cell suspension cultures under nutritional stress accumulated phenolic compounds and proline, at the same time their biomass production was negatively affected by nutrient deficiency. The results obtained strongly suggest that plant tissues respond to nutrient deprivation by a defensive costly mechanism, which determines the establishment of a mechanism of trade-off between growth and adaptive response. Furthermore, the results of this research suggest that perception of abiotic stress and increased phenolic metabolites are linked by a sequence of biochemical processes that also involves the intracellular free proline and the oxidative pentose phosphate pathway. The main conclusion of this paper is that, once calli and cell suspension cultures respond to nutrient deficiency, in acclimated cells the establishment of a negative correlation between primary metabolism (growth) and secondary metabolism (defence compounds) is observed. Copyright © 2018 Elsevier Masson SAS. All rights reserved.

  9. Production, secretion, and stability of human secreted alkaline phosphatase in tobacco NT1 cell suspension cultures.

    Science.gov (United States)

    Becerra-Arteaga, Alejandro; Mason, Hugh S; Shuler, Michael L

    2006-01-01

    Tobacco NT1 cell suspension cultures secreting active human secreted alkaline phosphatase (SEAP) were generated for the first time as a model system to study recombinant protein production, secretion, and stability in plant cell cultures. The SEAP gene encodes a secreted form of the human placental alkaline phosphatase (PLAP). During batch culture, the highest level of active SEAP in the culture medium (0.4 U/mL, corresponding to approximately 27 mg/L) was observed at the end of the exponential growth phase. Although the level of active SEAP decreased during the stationary phase, the activity loss did not appear to be due to SEAP degradation (based on Western blots) but due to SEAP denaturation. The protein-stabilizing agents polyvinylpirrolidone (PVP) and bacitracin were added extracellularly to test for their ability to reduce the loss of SEAP activity during the stationary phase. Bacitracin (100 mg/L) was the most effective treatment at sustaining activity levels for up to 17 days post-subculture. Commercially available human placental alkaline phosphatase (PLAP) was used to probe the mechanism of SEAP deactivation. Experiments with PLAP in sterile and conditioned medium corroborated the denaturation of SEAP by factors generated by cell growth and not due to simple proteolysis. We also show for the first time that the factors promoting activity loss are heat labile at 95 degrees C but not at 70 degrees C, and they are not inactivated after a 5 day incubation period under normal culture conditions (27 degrees C). In addition, there were no significant changes in pH or redox potential when comparing sterile and cell-free conditioned medium during PLAP incubation, indicating that these factors were unimportant.

  10. Enhanced production of phenolic acids in cell suspension culture of Salvia leriifolia Benth. using growth regulators and sucrose.

    Science.gov (United States)

    Modarres, Masoomeh; Esmaeilzadeh Bahabadi, Sedigheh; Taghavizadeh Yazdi, Mohammad Ehsan

    2018-04-01

    Salvia leriifolia Benth. (Lamiaceae) is an endangered medicinal plant with hypoglycemic, anti-inflammatory and analgesic properties. Many of the beneficial effects of Salvia spp. are attributed to the phenolic compounds. In the present study, an efficient procedure has been developed for establishment of cell suspension culture of S. leriifolia as a strategy to obtain an in vitro phenolic acids producing cell line for the first time. The effect of growth regulators and various concentrations of sucrose have been analyzed, to optimize biomass growth and phenolic acids production. The callus used for this purpose was obtained from leaves of 15-day-old in vitro seedlings, on Murashige and Skoog (MS) basal medium supplemented with different hormone balances including benzylaminopurine (BAP) and indole butyric acid (IBA); 2,4-dichlorophenoxyacetic acid (2,4-D) and kinetin (KIN); naphthaleneacetic acid (NAA) and BAP. Modified MS medium supplemented with 5 mg/L BAP and 5 mg/L NAA was the optimal condition for callus formation with the highest induction rate (100%), the best callus growth and the highest phenolic acids content. No callus induction was observed in combinations of IBA and BAP. Cell suspension cultures were established by transferring 0.5 g of callus to 30 mL liquid MS medium supplemented with 5 mg/L BAP and 5 mg/L NAA. Dynamics of phenolic acids production has been investigated during the growth cycle of the suspension cultures. The maximum content of caffeic acid and salvianolic acid B were observed on the 15th day of the cultivation cycle while the highest amount of rosmarinic acid was observed on the first day. In response to various sucrose concentrations, cell cultures with 40 g/L sucrose not only produced the highest dry biomass but also the highest induction of caffeic acid and salvianolic acid B. The highest amount of rosmarinic acid was observed in media containing 50 g/L sucrose. These prepared cell suspension cultures provided a useful

  11. Enhancement effect of shikonin in cell suspension culture and transfermanant culture by radiation application

    International Nuclear Information System (INIS)

    Kim, Jae Sung; Lee, Young Keun; Chung, Byung Yeoup; Lee, Young Bok; Hwang Hye Yeon

    2004-10-01

    The cell lines 679, 679-29 and 622-46 of L. erythrorhizon could be selected on LS agar medium for the production shikonin in cell suspension culture. The shikonin was increased moderately in suspension culture of cell line 622-46 in LS liquid medium containing BA 2 mg·L -1 and IAA 0.2 mg·L -1 in the dark, and was increased by adding 1 μM Cu 2+ and 100 μM methyl jasmonate The accumulation of shikonin in the liquid medium was increased significantly by 2 Gy irradiation to callus of cell line 622-46 and culture in LS liquid medium containing BA 2 mg·L -1 and IAA 0.2 mg·L -1 in the dark and shikonin in cell debris was higher by 16 Gy irradiation. The activity of p-hydroxybenzoate geranyltransferase was increased by irradiation of 2 Gy and 16 Gy of γ radiation. Seedling hypocotyles of L. erythrorhizon were infected with Agrogacterium rhizogenes strain 15834 harboring a binary vector with an intron bearing the GUS (β-glucuronidase) gene driven by cauliflower mosaic virus (CaMV) 35S promotor as well as the HPT (hygromycin phosphotransferase) gene as the selection marker. Hairy roots isolated were hygromycin resistant and had integrated GUS gene in DNA. The root tip grown on M-9 medium showed normal pigment production pattern in border cells and root hairs

  12. Changes in cell wall properties coincide with overexpression of extensin fusion proteins in suspension cultured tobacco cells.

    Science.gov (United States)

    Tan, Li; Pu, Yunqiao; Pattathil, Sivakumar; Avci, Utku; Qian, Jin; Arter, Allison; Chen, Liwei; Hahn, Michael G; Ragauskas, Arthur J; Kieliszewski, Marcia J

    2014-01-01

    Extensins are one subfamily of the cell wall hydroxyproline-rich glycoproteins, containing characteristic SerHyp4 glycosylation motifs and intermolecular cross-linking motifs such as the TyrXaaTyr sequence. Extensins are believed to form a cross-linked network in the plant cell wall through the tyrosine-derivatives isodityrosine, pulcherosine, and di-isodityrosine. Overexpression of three synthetic genes encoding different elastin-arabinogalactan protein-extensin hybrids in tobacco suspension cultured cells yielded novel cross-linking glycoproteins that shared features of the extensins, arabinogalactan proteins and elastin. The cell wall properties of the three transgenic cell lines were all changed, but in different ways. One transgenic cell line showed decreased cellulose crystallinity and increased wall xyloglucan content; the second transgenic cell line contained dramatically increased hydration capacity and notably increased cell wall biomass, increased di-isodityrosine, and increased protein content; the third transgenic cell line displayed wall phenotypes similar to wild type cells, except changed xyloglucan epitope extractability. These data indicate that overexpression of modified extensins may be a route to engineer plants for bioenergy and biomaterial production.

  13. Comparison of Cuminaldehyde Contents from Cell Suspension Cultures and Seeds of [Bunium persicum (Boiss. B. Fedtsch.

    Directory of Open Access Journals (Sweden)

    Sara KHOSRAVINIA

    2012-11-01

    Full Text Available The cell suspension culture and seed samples of Bunium persicum were extracted by supercritical fluid, hydrodistillation and solvent methods and analyzed by Gas Chromatography. In this study to compare the different methods of extractions, cuminaldehyde was targeted as one of the Black zira essential oil constitute. For callus induction the germinated seeds were cultured as explants on Murashige and Skoog medium supplemented with 2 mg/l 2,4-dichlorophenoxy acetic acid and 0.5 mg/l kinetin (treatment A as well as 2 mg/l ?-naphthalene acetic acid and 0.5 mg/l 6-benzyl aminopurine (treatment B and followed by cells suspension cultures establishment for the first time. The results of cell culture showed that cells from treatment B have a growth rate higher than A. All extracts were dissolved in 1 ml hexane and analyzed by Gas Chromatography. According to the Gas Chromatography analysis, cuminaldehyde was not detected in the supercritical fluid samples, while it was present in hydrodistillation and solvent extract. Cuminaldehyde percentage in cell and seed solvent extracts was 4.65% and 18.61% respectively. Gas Chromatography results also showed that no cuminaldehyde is present in media extracts, means no cuminaldehyde has been secreted into the medium.

  14. Effect of terbinafine on the biosynthetic pathway of isoprenoid compounds in carrot suspension cultured cells.

    Science.gov (United States)

    Miras-Moreno, Begoña; Almagro, Lorena; Pedreño, María Angeles; Sabater-Jara, Ana Belén

    2018-04-21

    cell cultures treated with cyclodextrins or terbinafine were able to produce high levels of phytosterols and squalene, respectively, and, therefore, these suspension-cultured cells of carrot constitute an alternative biotechnological system, which is at the same time more sustainable, economic and ecological for the production of these bioactive compounds.

  15. Induction of sesquiterpenoid biosynthesis in tobacco cell suspension cultures by fungal elicitor

    International Nuclear Information System (INIS)

    Chappell, J.; Nable, R.

    1987-01-01

    Large amounts of the sesquiterpenoid capsidiol accumulated in the media of tobacco (Nicotiana tabacum L. cv KY14) cell suspension cultures upon addition of fungal elicitor. Capsidiol accumulation was proportional to the amount of elicitor added. The accumulation of capsidiol was preceded by a transient increase in the capsidiol de novo synthesis rate as measured by the incorporation of exogenous [ 14 C]acetate. Changes in 3-hydroxy-3-methylglutaryl-CoA reductase activity, an enzyme of general isoprenoid metabolism, paralleled the changes in [ 14 C]acetate incorporation into capsidiol. Incubation of the cell cultures with mevinolin, a potent in vitro inhibitor of the tobacco HMGR enzyme activity, inhibited the elicitor-induced capsidiol accumulation in a concentration dependent manner. [ 14 C]Acetate incorporation into capsidiol was likewise inhibited by mevinolin treatment. Unexpectedly, [ 3 H] mevalonate incorporation into capsidiol was also partially inhibited by mevinolin, suggesting that mevinolin may effect secondary sites of sesquiterpenoid biosynthesis in vivo beyond HMGR. The data indicated the importance of the induced HMGR activity for capsidiol production in elicitor-treated tobacco cell suspension cultures

  16. Differentiation of Human Pluripotent Stem Cells into Functional Endothelial Cells in Scalable Suspension Culture

    Directory of Open Access Journals (Sweden)

    Ruth Olmer

    2018-05-01

    Full Text Available Summary: Endothelial cells (ECs are involved in a variety of cellular responses. As multifunctional components of vascular structures, endothelial (progenitor cells have been utilized in cellular therapies and are required as an important cellular component of engineered tissue constructs and in vitro disease models. Although primary ECs from different sources are readily isolated and expanded, cell quantity and quality in terms of functionality and karyotype stability is limited. ECs derived from human induced pluripotent stem cells (hiPSCs represent an alternative and potentially superior cell source, but traditional culture approaches and 2D differentiation protocols hardly allow for production of large cell numbers. Aiming at the production of ECs, we have developed a robust approach for efficient endothelial differentiation of hiPSCs in scalable suspension culture. The established protocol results in relevant numbers of ECs for regenerative approaches and industrial applications that show in vitro proliferation capacity and a high degree of chromosomal stability. : In this article, U. Martin and colleagues show the generation of hiPSC endothelial cells in scalable cultures in up to 100 mL culture volume. The generated ECs show in vitro proliferation capacity and a high degree of chromosomal stability after in vitro expansion. The established protocol allows to generate hiPSC-derived ECs in relevant numbers for regenerative approaches. Keywords: hiPSC differentiation, endothelial cells, scalable culture

  17. Uptake and metabolism of sugars by suspension-cultured catharanthus roseus cells

    International Nuclear Information System (INIS)

    Ashihara, Hiroshi; Sagishima, Kyoko; Kubota, Kaoru

    1989-01-01

    The Uptake and metabolism of sugars by suspension-cultured Catharanthus roseus cells were investigated. Substantially all the sucrose in the culture medium was hydrolyzed to glucose and fructose before being taken up by the cells. The activity of invertase bound to cell walls, determined in situ, was high at the early stage of culture. Glucose was more easily taken up by the cells than was fructose. Tracer experiments using [U- 14 C]glucose and [U- 14 C]fructose indicated that glucose is a better precursor for respiration than fructose, while fructose is preferentially utilized for the synthesis of sucrose, especially in the early phase of cell growth. These results suggest that fructose is utilized for the synthesis of sucrose via the reaction catalyzed by sucrose synthase, prior to the phosphorylation by hexokinase or fructokinase

  18. Impact of fluidic agitation on human pluripotent stem cells in stirred suspension culture.

    Science.gov (United States)

    Nampe, Daniel; Joshi, Ronak; Keller, Kevin; Zur Nieden, Nicole I; Tsutsui, Hideaki

    2017-09-01

    The success of human pluripotent stem cells (hPSCs) as a source of future cell therapies hinges, in part, on the availability of a robust and scalable culture system that can readily produce a clinically relevant number of cells and their derivatives. Stirred suspension culture has been identified as one such promising platform due to its ease of use, scalability, and widespread use in the pharmaceutical industry (e.g., CHO cell-based production of therapeutic proteins) among others. However, culture of undifferentiated hPSCs in stirred suspension is a relatively new development within the past several years, and little is known beyond empirically optimized culture parameters. In particular, detailed characterizations of different agitation rates and their influence on the propagation of hPSCs are often not reported in the literature. In the current study, we systematically investigated various agitation rates to characterize their impact on cell yield, viability, and the maintenance of pluripotency. Additionally, we closely examined the distribution of cell aggregates and how the observed culture outcomes are attributed to their size distribution. Overall, our results showed that moderate agitation maximized the propagation of hPSCs to approximately 38-fold over 7 days by keeping the cell aggregates below the critical size, beyond which the cells are impacted by the diffusion limit, while limiting cell death caused by excessive fluidic forces. Furthermore, we observed that fluidic agitation could regulate not only cell aggregation, but also expression of some key signaling proteins in hPSCs. This indicates a new possibility to guide stem cell fate determination by fluidic agitation in stirred suspension cultures. Biotechnol. Bioeng. 2017;114: 2109-2120. © 2017 Wiley Periodicals, Inc. © 2017 Wiley Periodicals, Inc.

  19. Jasmonic and salicylic acids enhanced phytochemical production and biological activities in cell suspension cultures of spine gourd (Momordica dioica Roxb).

    Science.gov (United States)

    Chung, Ill-Min; Rekha, Kaliyaperumal; Rajakumar, Govindasamy; Thiruvengadam, Muthu

    2017-03-01

    In vitro cell suspension culture was established for the production of commercially valuable phytochemicals in Momordica dioica. The influence of elicitors in jasmonic acid (JA) and salicylic acid (SA) increased their effect on phytochemical production and biomass accumulation in M. dioica. The results indicate that compared with non-elicited cultures, JA- and SA-elicited cell suspension cultures had significantly enhanced phenolic, flavonoid, and carotenoid production, as well as antioxidant, antimicrobial, and antiproliferative activities. Furthermore, elicited cultures produced 22 phenolic compounds, such as flavonols, hydroxycinnamic acids, and hydroxybenzoic acids. Greater biomass production, phytochemical accumulation, and biological activity occurred in JA- than in SA-elicited cell cultures. This study is the first to successfully establish M. dioica cell suspension cultures for the production of phenolic compounds and carotenoids, as well as for biomass accumulation.

  20. Production of Monascus pigments as extracellular crystals by cell suspension culture.

    Science.gov (United States)

    Lu, Fengling; Liu, Lujie; Huang, Yaolin; Zhang, Xuehong; Wang, Zhilong

    2018-01-01

    It is generally accepted that Monascus pigments are predominantly cell-bound, including both intracellular and surface-bound pigments. This long-term misconception was corrected in the present work. Production of extracellular crystal pigments by submerged culture of Monascus sp. was confirmed by microscopic observation and collection of Monascus pigments from extracellular broth by direct membrane filtration. Following up the new fact, the bioactivity of mycelia as whole-cell biocatalyst for biosynthesis and biodegradation of Monascus pigments had been detailedly examined in both an aqueous solution and a nonionic surfactant micelle aqueous solution. Based on those experimental results, cell suspension culture in an aqueous medium was developed as a novel strategy for accumulation of high concentration of Monascus pigments. Thus, glucose feeding during submerged culture in the aqueous medium was carried out successfully and high orange Monascus pigments concentration of near 4 g/L was achieved.

  1. Metabolism of pentachlorophenol in cell suspension cultures of wheat (Triticum aestivum L.). Tetrachlorocatechol as a primary metabolite

    International Nuclear Information System (INIS)

    Schaefer, W.; Sandermann, H. Jr.

    1988-01-01

    Wheat cell suspension cultures were incubated with [U- 14 C] pentachlorophenol (PCP; 1 ppm, 48 h, 27 0 C). Soluble metabolites were formed in ∼ 50% yield, another ∼ 31% of the applied radioactivity being incorporated into the insoluble residue. The soluble metabolite fraction, and its β-D-glucoside conjugate components, the total insoluble residue, and its lignin components, were all found to contain a novel polar PCP derivative besides smaller amounts of tetrachlorohydroquinone and PCP. The novel derivative also predominated in intact wheat plants and was identified as tetrachlorocatechol by TLC, HPLC, GC, and EI as well as CI mass spectroscopy. Tetrachlorocatechol is a potential mutagen, so that the soluble and insoluble conjugates formed in wheat from PCP may present a toxicological hazard

  2. Increased podophyllotoxin production in Podophyllum hexandrum cell suspension cultures after feeding coniferyl alcohol as a β-cyclodextrin complex

    NARCIS (Netherlands)

    Woerdenbag, H.J.; Van Uden, W.; Frijlink, H.W.; Lerk, C.F.; Pras, N.; Malingre, T.M.

    1990-01-01

    Cell suspension cultures, derived from roots of Podophyllum hexandrum Royle (Berberidaceae), accumulate podophyllotoxin. In this study the use of β-cyclodextrin in feeding the poorly water-soluble precursor coniferyl alcohol to these cultures is described. By complexation with β-cyclodextrin, a

  3. Increased podophyllotoxin production in Podophyllum hexandrum cell suspension cultures after feeding coniferyl alcohol as a β-cyclodextrin complex

    NARCIS (Netherlands)

    Woerdenbag, H J; van Uden, W; Frijlink, H W; Lerk, C F; Pras, N; Malingré, T M

    Cell suspension cultures, derived from roots of Podophyllum hexandrum Royle (Berberidaceae), accumulate podophyllotoxin. In this study the use of β-cyclodextrin in feeding the poorly water-soluble precursor coniferyl alcohol to these cultures is described. By complexation with β-cyclodextrin, a

  4. Aggregate formation and suspension culture of human pluripotent stem cells and differentiated progeny.

    Science.gov (United States)

    Hookway, Tracy A; Butts, Jessica C; Lee, Emily; Tang, Hengli; McDevitt, Todd C

    2016-05-15

    Culture of human pluripotent stem cells (hPSC) as in vitro multicellular aggregates has been increasingly used as a method to model early embryonic development. Three-dimensional assemblies of hPSCs facilitate interactions between cells and their microenvironment to promote morphogenesis, analogous to the multicellular organization that accompanies embryogenesis. In this paper, we describe a method for reproducibly generating and maintaining populations of homogeneous three-dimensional hPSC aggregates using forced aggregation and rotary orbital suspension culture. We propose solutions to several challenges associated with the consistent formation and extended culture of cell spheroids generated from hPSCs and their differentiated progeny. Further, we provide examples to demonstrate how aggregation can be used as a tool to select specific subpopulations of cells to create homotypic spheroids, or as a means to introduce multiple cell types to create heterotypic tissue constructs. Finally, we demonstrate that the aggregation and rotary suspension method can be used to support culture and maintenance of hPSC-derived cell populations representing each of the three germ layers, underscoring the utility of this platform for culturing many different cell types. Copyright © 2015 Elsevier Inc. All rights reserved.

  5. Cell suspension culture and mutants selection for resistance to PEG induced water stress in alfalfa (Medicago sativa L.)

    International Nuclear Information System (INIS)

    Zhang Xiaodong; Lin Tingan

    1994-01-01

    Elements affecting suspension cell culture in alfalfa (Medicago sativa L.) were studied and a method of rapid establishment of embryogenic suspension cell lines was introduced. Effects of γ ray irradiation on the growth of suspension cells were studied, and the optimum dose of irradiation for inducing mutants from suspension cells was about 20 ∼ 60 Gy. Effects of PEG and NaCl induced water stress on the growth of suspension cells were also investigated, and the results showed that the congregants of preliminary suspension culture were more susceptible than the established suspension cell lines. With 20 Gy of γ ray irradiation on suspension cell line (JL416), six clones were obtained with 70 days of selection on medium of 15% PEG (about-11 bar). A number of regenerated plants were obtained from these clones. One clone was also gained from medium containing 20% PEG (about-15 bar). The selected mutant cell lines (JP15 and JP20) has strong resistances to high concentration of PEG and NaCl induced water stress

  6. Three sesquiterpene compounds biosynthesised from artemisinic acid using suspension-cultured cells of Averrhoa carambola (Oxalidaceae).

    Science.gov (United States)

    Yang, Li; Zhu, Jianhua; Song, Liyan; Shi, Xiaojian; Li, Xingyi; Yu, Rongmin

    2012-01-01

    A new sesquiterpene glycoside, artemisinic acid 3-β-O-β-D-glucopyranoside (3, 31.24%) and other two biotransformation products, 3-β-hydroxyartemisinic acid (2, 36.69%) and 3-β-hydroxyartemisinic acid β-D-glucopyranosyl ester (4, 7.03%), were biosynthesised after artemisinic acid (1) was administered to the cultured cells of Averrhoa carambola. The three biotransformation products were obtained for the first time by using the suspension-cultured cells of A. carambola as a new biocatalyst system, and their structures were identified on the basis of the physico-chemical properties, NMR and mass spectral analyses. The results indicate that the cultured cells of A. carambola have the abilities to hydroxylate and glycosylate sesquiterpene compounds in a regio- and stereoselective manner. Furthermore, the anti-tumour activity of compounds 3 and 4 was evaluated against K562 and HeLa cell lines. Compound 4 showed strong activity against HeLa cell line, with the IC₅₀ value of 0.56 µmol mL⁻¹.

  7. Elicitation of Jerusalem artichoke (Helianthus tuberosus L.) cell suspension culture for enhancement of inulin production and altered degree of polymerisation.

    Science.gov (United States)

    Ma, Chunquan; Zhou, Dong; Wang, Haitao; Han, Dongming; Wang, Yang; Yan, Xiufeng

    2017-01-01

    Plant cell suspension cultures have emerged as a potential source of secondary metabolites for food additives and pharmaceuticals. In this study inulin accumulation and its degree of polymerisation (DP) in the treated cells in the same medium were investigated after treatment with six types of elicitors. An in vitro cell suspension culture of Jerusalem artichoke (Helianthus tuberosus L.) was optimised by adding an extra nitrogen source. According to the growth kinetics, a maximum biomass of 5.48 g L -1 was obtained from the optimal cell suspension medium consisted of Murashige and Skoog basic medium (MS) + 1.0 mg L -1 α-naphthalene acetic acid (NAA) + 1.0 mg L -1 6-benzylaminopurine (6-BA) + 0.5 mg L -1 proline + 1.0 mg L -1 glutamine. Methyl jasmonate (MeJA, 250 µmol L -1 ) treatment for 15 days led to the highest levels of inulin (2955.27 ± 9.81 mg L -1 compared to control of 1217.46 ± 0.26 mg L -1 ). The elicited effect of five elicitors to the suspension cells of Jerusalem artichoke is as follows: AgNO 3 (Ag, 10 µmol L -1 ), salicylic acid (SA, 75 µmol L -1 ), chitosan (KJT, 40 mg L -1 ), Trichoderma viride (Tv, 90 mg L -1 ), yeast extract (YE, 0.25 mg L -1 ), and the corresponding content of inulin is increased by 2.05-, 1.93-, 1.76-, 1.44- and 1.18-fold compared to control, respectively. The obvious effect on the percentage of lower DP in inulin was observed in cells treated with 40 mg L -1 KJT, 0.25 mg L -1 YE and 10 µmol L -1 Ag. Among the six types of elicitors, the descending order of inulin content is MeJA > Ag > SA > KJT > Tv > YE. For the purpose inulin with lower DP and its application to prebiotic food, three elicitors, including KJT, YE and Ag, can be used for the elicitation. © 2016 Society of Chemical Industry. © 2016 Society of Chemical Industry.

  8. Stereoselectivity of the demethylation of nicotine piperidine homologues by Nicotiana plumbaginifolia cell suspension cultures.

    Science.gov (United States)

    Bartholomeusz, Trixie Ann; Molinié, Roland; Roscher, Albrecht; Felpin, François-Xavier; Gillet, Françoise; Lebreton, Jacques; Mesnard, François; Robins, Richard J

    2005-08-01

    The metabolism of (R,S)-N-methylanabasine and (R,S)-N-methylanatabine has been studied in a cell suspension culture of Nicotiana plumbaginifolia. Both substrates are effectively demethylated, anabasine or anatabine, respectively, accumulating in the medium. Similarly, there is strong stereoselectivity for the (R)-isomers of both substrates. The kinetics of metabolism of (R,S)-N-methylanabasine differ significantly from those of nicotine in that no further degradation of the initial demethylation product occurs. (R,S)-N-Methylanatabine, however, shows kinetics closer to those of nicotine, with loss of alkaloid from the system. Further more, (R,S)-N-methylanabasine does not diminish (S)-nicotine demethylation, indicating a lack of competition. However, the metabolism of (S)-nicotine is affected by the presence of (R,S)-N-methylanabasine. Hence, the demethylation of the piperidine homologues of nicotine is seen to be similar but not identical to that of the pyridine analogues. The implications of these different metabolic profiles in relation to the demethylation activity are discussed.

  9. Treatment strategies for high resveratrol induction in Vitis vinifera L. cell suspension culture

    Directory of Open Access Journals (Sweden)

    Thu V. Vuong

    2014-06-01

    Full Text Available Bioprocesses capable of producing large scales of resveratrol at nutraceutical grade are in demand. This study herein investigated treatment strategies to induce the production of resveratrol in Vitis vinifera L. cell suspension cultures. Among seven investigated elicitors, jasmonic acid (JA, salicylic acid, β-glucan (GLU, and chitosan enhanced the production of intracellular resveratrol manyfold. The combined treatment of JA and GLU increased extracellular resveratrol production by up to tenfold. The application of Amberlite XAD-7 resin for in situ removal and artificial storage of secreted resveratrol further increased resveratrol production by up to four orders of magnitude. The level of resveratrol produced in response to the combined treatment with 200 g/L XAD-7, 10 μM JA and 1 mg/mL GLU was approximately 2400 mg/L, allowing the production of resveratrol at an industrial scale. The high yield of resveratrol is due to the involvement of a number of mechanisms working in concert.

  10. Proteins differentially expressed in elicited cell suspension culture of Podophyllum hexandrum with enhanced podophyllotoxin content

    Directory of Open Access Journals (Sweden)

    Bhattacharyya Dipto

    2012-05-01

    Full Text Available Abstract Background Podophyllotoxin (PTOX, the precursor for semi-synthesis of cancer therapeutics like etoposide, teniposide and etophos, is primarily obtained from an endangered medicinal herb, Podophyllum hexandrum Royle. PTOX, a lignan is biosynthetically derived from the phenylpropanoid pathway. The aim of this study is to investigate changes in the P. hexandrum cell proteome potentially related to PTOX accumulation in response to methyl jasmonate (MeJA elicitation. High-resolution two-dimensional gel electrophoresis (2-DE followed by colloidal Coomassie staining and mass spectrometric analysis was used to detect statistically significant changes in cell’s proteome. Result The HPLC analysis showed approximately 7–8 fold change in accumulation of PTOX, in the 12day old cell suspension culture (i.e. after 9days of elicitation elicited with 100 μM MeJA as compared to the control. Using 2-DE a total of 233 spots was detected, out of which 105 spots were identified by MALDI TOF-TOF MS/MS. Data were subjected to functional annotation from a biological point of view through KEGG. The phenylpropanoid and monolignol pathway enzymes were identified, amongst these, chalcone synthase, polyphenol oxidase, caffeoyl CoA 3-O-methyltransferase, S-adenosyl-L-methionine-dependent methyltransferases, caffeic acid-O-methyl transferase etc. are noted as important. The relation of other differentially accumulated proteins with varied effects caused by elicitors on P. hexandrum cells namely stress and defense related protein, transcription and DNA replication and signaling are also discussed. Conclusions Elicitor-induced PTOX accumulation in P. hexandrum cell cultures provides a responsive model system to profile modulations in proteins related to phenylpropanoid/monolignol biosynthesis and other defense responses. Present findings form a baseline for future investigation on a non-sequenced medicinal herb P. hexandrum at molecular level.

  11. Role of Changes in Cell Fatty Acids Composition in the Increasing of Frost Resistance of Winter Wheat Suspension Culture

    Directory of Open Access Journals (Sweden)

    I.V. Lyubushkina

    2013-11-01

    Full Text Available Influences of low temperatures (4 and 8 ° С on the frost tolerance and fatty acid compositions of cells in a winter wheat suspension culture have been studied. It has been found that treatment of the culture with 4 °C (7 days did not protect cells from subsequent freezing temperature action (-8 °С, 6 h and was not accompanied significant changes in the fatty acid composition. On the contrary, the treatment of the culture with the temperature 8 °C (7 days prevented the death caused by freezing temperature and the content of saturated fatty acids decreased: pentadecanoic acid (by 35,0%, palmitic acid (by 19,9% and stearic acid (by 65,4%, and the content of α-linolenic acid increased by 94%. That was the cause of the double bond index (DBI increase by 16%. The role of fatty acids composition changes in the process of increasing frost tolerance in plants are discussed.

  12. Effect of sucrose and methyl jasmonate on biomass and anthocyanin production in cell suspension culture of Melastoma malabathricum (Melastomaceae

    Directory of Open Access Journals (Sweden)

    Koay Suan See

    2011-06-01

    Full Text Available Melastoma malabathricum, belongs to the Melastomaceae family, is an important medicinal plant widely distributed from Madagascar to Australia, that is used in traditional remedies for the treatment of variousailments. Besides its medicinal properties, it has been identified as a potential source of anthocyanin production.The present study was carried out to investigate the effect of sucrose and methyl jasmonate and feeding time oncell biomass yield and anthocyanin production in cell suspension culture of M. malabathricum. Addition of differentconcentrations of sucrose into the cell culture of M. malabathricum influenced cell biomass and pigment accumulation. The addition of methyl jasmonate was found to have no effect on cell biomass but the presence of higher amount (12.5-50mg/L had caused a reduction in anthocyanin production and accumulation. MS medium supplemented with 30g/L sucrose and 3.5 mg/L of MeJA added on cero day and 3rd day produced high fresh cell mass at the end of nine days of culture but did not support the production of anthocyanins. However, cells cultured in the medium supplemented with 45g/L sucrose without MeJA showed the highest pigment content (0.69±0.22Cv/g-FCM. The cells cultured in MS medium supplemented with 30 g/L sucrose with 3.5mg/L MeJA added on the 3rd and 6th day of culture, showed the lowest pigment content (0.37-0.40Cv/g-FCM. This study indicated that MeJA was not necessary but sucrose was needed for the enhancement of cell growth and anthocyanin production in M. malabathricum cell cultures. Rev. Biol. Trop. 59 (2: 597-606. Epub 2011 June 01.

  13. Induction of Shikimic Acid Pathway Enzymes by Light in Suspension Cultured Cells of Parsley (Petroselinum crispum) 1

    Science.gov (United States)

    McCue, Kent F.; Conn, Eric E.

    1990-01-01

    Light treatment of suspension cultured cells of parsley (Petroselinum crispum) was shown to increase the activity of the shikimic acid pathway enzyme, 3-deoxy-d-arabino-heptulosonic acid-7-phosphate (DAHP) synthase (EC 4.1.2.15). DAHP synthase activity was assayed for two isoforms, DS-Mn and DS-Co (RJ Ganson, TA d'Amato, RA Jensen [1986] Plant Physiol 82: 203-210). Light increased the enzymatic activity of the plastidic isoform DS-Mn as much as 2-fold, averaging 1.6-fold with >95% confidence. The cytosolic isoform DS-Co was unaffected. Cycloheximide and actinomycin D, translational and transcriptional inhibitors, respectively, both reversed induction of DS-Mn by light suggesting transcriptional regulation of the gene. Chorismate mutase activity was assayed for the two isoforms CM I and CM II (BK Singh, JA Connelly, EE Conn [1985] Arch Biochem Biophys 243: 374-384). Treatment by light did not significantly affect either chorismate mutase isoform. The ratio of the two chorismate mutase isoforms changed during the growth cycle, with an increase in the ratio of plastidic to cytosolic isoforms occurring towards the end of logarithmic growth. PMID:16667741

  14. Suicidal tomato cells: programmed cell death in suspension-cultured tomato cells and ripening fruit

    NARCIS (Netherlands)

    Hoeberichts, F.A.

    2002-01-01

    Tomato fruit ripening involves a series of highly organised biochemical, physiological and structural changes that are under strict genetic control. The plant hormone ethylene (C 2 H 4 ), in synergy

  15. Enhanced resveratrol production in Vitis vinifera cell suspension cultures by heavy metals without loss of cell viability.

    Science.gov (United States)

    Cai, Zhenzhen; Kastell, Anja; Speiser, Claire; Smetanska, Iryna

    2013-09-01

    The effects of heavy metal ions (Co(2+), Ag(+), Cd(2+)) on cell viability and secondary metabolite production, particularly anthocyanins and phenolic acids in Vitis vinifera cell suspension cultures, were investigated. Of these, Co at all three used concentrations (5.0, 25, and 50 μM), Ag, and Cd at low concentration (5.0 μM) were most effective to stimulate the phenolic acid production, increasing the 3-O-glucosyl-resveratrol up to 1.6-fold of the control level (250.5 versus 152.4 μmol/g), 4 h after the treatments. Meanwhile, the elicitors at effective concentrations did not suppress cell growth, while the cell viability maintained. In contrast, Ag and Cd at high concentrations (25 and 50 μM) remarkably reduced the cell viability, decreasing the cell viability up to about 15 % of the control level, 24 h after the treatments. The heavy metal ions did not affect the anthocyanin production. These observations show how, in a single system, different groups of secondary products can show distinct differences in their responses to potential elicitors. The 1,1-diphenyl-2-picrylhydrazyl radical scavenging activity, peroxidase activity, medium pH value, and conductivity were only slightly elevated by the heavy metal ions. The results suggest that some of the secondary metabolites production was stimulated by the used elicitors, but there was not a stress response of the cells.

  16. Biosynthesis of 14C-phytoene from tomato cell suspension cultures (Lycopersicon esculentum) for utilization in prostate cancer cell culture studies.

    Science.gov (United States)

    Campbell, Jessica K; Rogers, Randy B; Lila, Mary Ann; Erdman, John W

    2006-02-08

    This work describes the development and utilization of a plant cell culture production approach to biosynthesize and radiolabel phytoene and phytofluene for prostate cancer cell culture studies. The herbicide norflurazon was added to established cell suspension cultures of tomato (Lycopersicon esculentum cv. VFNT cherry), to induce the biosynthesis and accumulation of the lycopene precursors, phytoene and phytofluene, in their natural isomeric forms (15-cis-phytoene and two cis-phytofluene isomers). Norflurazon concentrations, solvent carrier type and concentration, and duration of culture exposure to norflurazon were screened to optimize phytoene and phytofluene synthesis. Maximum yields of both phytoene and phytofluene were achieved after 7 days of treatment with 0.03 mg norflurazon/40 mL fresh medium, provided in 0.07% solvent carrier. Introduction of 14C-sucrose to the tomato cell culture medium enabled the production of 14C-labeled phytoene for subsequent prostate tumor cell uptake studies. In DU 145 prostate tumor cells, it was determined that 15-cis-phytoene and an oxidized product of phytoene were taken up and partially metabolized by the cells. The ability to biosynthesize, radiolabel, and isolate these carotenoids from tomato cell cultures is a novel, valuable methodology for further in vitro and in vivo investigations into the roles of phytoene and phytofluene in cancer chemoprevention.

  17. Simple suspension culture system of human iPS cells maintaining their pluripotency for cardiac cell sheet engineering.

    Science.gov (United States)

    Haraguchi, Yuji; Matsuura, Katsuhisa; Shimizu, Tatsuya; Yamato, Masayuki; Okano, Teruo

    2015-12-01

    In this study, a simple three-dimensional (3D) suspension culture method for the expansion and cardiac differentiation of human induced pluripotent stem cells (hiPSCs) is reported. The culture methods were easily adapted from two-dimensional (2D) to 3D culture without any additional manipulations. When hiPSCs were directly applied to 3D culture from 2D in a single-cell suspension, only a few aggregated cells were observed. However, after 3 days, culture of the small hiPSC aggregates in a spinner flask at the optimal agitation rate created aggregates which were capable of cell passages from the single-cell suspension. Cell numbers increased to approximately 10-fold after 12 days of culture. The undifferentiated state of expanded hiPSCs was confirmed by flow cytometry, immunocytochemistry and quantitative RT-PCR, and the hiPSCs differentiated into three germ layers. When the hiPSCs were subsequently cultured in a flask using cardiac differentiation medium, expression of cardiac cell-specific genes and beating cardiomyocytes were observed. Furthermore, the culture of hiPSCs on Matrigel-coated dishes with serum-free medium containing activin A, BMP4 and FGF-2 enabled it to generate robust spontaneous beating cardiomyocytes and these cells expressed several cardiac cell-related genes, including HCN4, MLC-2a and MLC-2v. This suggests that the expanded hiPSCs might maintain the potential to differentiate into several types of cardiomyocytes, including pacemakers. Moreover, when cardiac cell sheets were fabricated using differentiated cardiomyocytes, they beat spontaneously and synchronously, indicating electrically communicative tissue. This simple culture system might enable the generation of sufficient amounts of beating cardiomyocytes for use in cardiac regenerative medicine and tissue engineering. Copyright © 2013 John Wiley & Sons, Ltd.

  18. Structural characterisation of xyloglucan secreted by suspension-cultured cells of Nicotiana plumbaginifolia.

    Science.gov (United States)

    Sims, I M; Munro, S L; Currie, G; Craik, D; Bacic, A

    1996-10-31

    Linkage analysis of a xyloglucan from the extracellular medium of suspension cultures of Nicotiana plumbaginifolia showed mostly 4-Glcp and 4,6-Glcp, terminal Xylp and 2-Xylp, and terminal Araf, along with approximately 10% (w/w) O-acetyl groups, equivalent to approximately 0.28 mol acetyl per mol of glycosyl residue. Methylation with methyl trifluoromethanesulfonate under neutral conditions, followed by re-methylation with CD3I under basic conditions, and conversion into partially methylated alditol acetates showed that O-acetyl groups were primarily attached to C-6 of approximately 44% of the 4-Glcp backbone not substituted with Xylp residues and to C-5 of approximately 15% of the terminal Araf residues. These positions of the O-acetyl groups were confirmed by 1H-NMR. Oligosaccharides generated by digestion of native xyloglucan with endo-(1-->4)-beta-glucanase were separated by a combination of gel-filtration chromatography and anion-exchange HPLC, and analysed by glycosyl linkage analysis and by electrospray ionisation-mass spectrometry (ESI-MS). The major oligosaccharide subunits were Glc4Xyl2 and Glc5Xyl2, of which 50-60% are substituted with one terminal Araf residue attached to O-2 of a Xylp residue, and a further 20-25% are substituted with two terminal Araf residues attached to O-2 of the Xylp residues. ESI-MS showed that many of the oligosaccharide subunits carried one, two, and, occasionally three O-acetyl groups.

  19. Biotransformation of artemisinin using cell suspension cultures of Catharanthus roseus (L.) G.Don and Lavandula officinalis L.

    Science.gov (United States)

    Patel, Suman; Gaur, Rashmi; Verma, Priyanka; Bhakuni, Rajendra S; Mathur, Archana

    2010-08-01

    Artemisinin, an antimalarial compound, at 5 mg/40 ml, was transformed by cell suspension cultures of Catharanthus roseus (L.) G.Don and Lavandula officinalis L. into deoxyartemisinin with yields >78% (3.93 mg deoxyartemisinin from 5 mg artemisinin). Maximum conversion (78.6 and 78%) occurred after 6 and 7 days of adding artemisinin to 20 and 9 days old cultures of C. roseus and L. officinalis, respectively. The procedure was scaled up by and 500 mg artemisinin was transformed into 390 mg deoxyartemisinin. Addition of artemisinin at the beginning of the culture cycle resulted in >50% reduction in dry biomass production with no bioconversion. Conversion of artemisinin occurred intracellularly followed by leaching of the product into the medium.

  20. High-level production of human interleukin-10 fusions in tobacco cell suspension cultures

    Science.gov (United States)

    Kaldis, Angelo; Ahmad, Adil; Reid, Alexandra; McGarvey, Brian; Brandle, Jim; Ma, Shengwu; Jevnikar, Anthony; Kohalmi, Susanne E; Menassa, Rima

    2013-01-01

    The production of pharmaceutical proteins in plants has made much progress in recent years with the development of transient expression systems, transplastomic technology and humanizing glycosylation patterns in plants. However, the first therapeutic proteins approved for administration to humans and animals were made in plant cell suspensions for reasons of containment, rapid scale-up and lack of toxic contaminants. In this study, we have investigated the production of human interleukin-10 (IL-10) in tobacco BY-2 cell suspension and evaluated the effect of an elastin-like polypeptide tag (ELP) and a green fluorescent protein (GFP) tag on IL-10 accumulation. We report the highest accumulation levels of hIL-10 obtained with any stable plant expression system using the ELP fusion strategy. Although IL-10-ELP has cytokine activity, its activity is reduced compared to unfused IL-10, likely caused by interference of ELP with folding of IL-10. Green fluorescent protein has no effect on IL-10 accumulation, but examining the trafficking of IL-10-GFP over the cell culture cycle revealed fluorescence in the vacuole during the stationary phase of the culture growth cycle. Analysis of isolated vacuoles indicated that GFP alone is found in vacuoles, while the full-size fusion remains in the whole-cell extract. This indicates that GFP is cleaved off prior to its trafficking to the vacuole. On the other hand, IL-10-GFP-ELP remains mostly in the ER and accumulates to high levels. Protein bodies were observed at the end of the culture cycle and are thought to arise as a consequence of high levels of accumulation in the ER. PMID:23297698

  1. Increased sesquiterpenoid biosynthesis and an apparent decrease in sterol biosynthesis in elicitor-treated tobacco cell suspension cultures

    International Nuclear Information System (INIS)

    Voegeli, U.; Bhatt, P.N.; Chappell, J.

    1987-01-01

    Addition of fungel elicitor prepared from Phytophthora parasitica to tobacco cell suspension cultures leads to an increased production of the phytoalexin capsidiol. Capsidiol is a sesquiterpenoid which is most likely synthesized from farnesylpyrophosphat (FPP) by a bicyclic cyclase reaction. Because FPP is also a substrate for squalene synthetase and therefore a precursor of sterol biosynthesis, the question arises whether or not the accumulation of capsidiol in elicitor-treated cells occurs at the expense of sterol biosynthesis. ( 14 C]-acetate was given to elicitor-treated and control (no treatment) cell cultures and incorporation into sterols and capsidiol determined. No labeled capsidiol was detected in control cells. In elicitor-treated cells about 12-15% of the radioactivity taken up by the cells was incorporated into capsidiol. In contrast, control cells incorporated 4 times more radioactivity into sterols than elicitor-treated cells. Similar results were obtained using ( 3 H)-mevalonate as a precursor of capsidiol and sterol biosynthesis. Likely explanations for the apparently decline in sterol biosynthesis in elicitor-treated cells include: (1) inhibition of squalene synthetase; (2) induction of capsidiol synthesizing enzymes; and (3) metabolic channeling of FPP into capsidiol versus sterols. These possibilities will be discussed further together with other results

  2. Changes in phytochelatins and their biosynthetic intermediates in red spruce (Picea rubens Sarg.) cell suspension cultures under cadmium and zinc stress

    Science.gov (United States)

    P. Thangavel; Stephanie Long; Rakesh Minocha

    2007-01-01

    Cell suspension cultures of red spruce (Picea rubens Sarg.) were selected to study the effects of cadmium (Cd) and zinc (Zn) on phytochelatins (PCs) and related metabolites after 24 h exposure. The PC2 and its precursor, γ-glutamylcysteine (γ-EC) increased two to fourfold with Cd concentrations ranging from 12...

  3. Cell suspension culture-mediated incorporation of the rice bel gene into transgenic cotton.

    Directory of Open Access Journals (Sweden)

    Liping Ke

    Full Text Available Cotton plants engineered for resistance to the herbicides, glyphosate or glufosinate have made a considerable impact on the production of the crop worldwide. In this work, embryogenic cell cultures derived from Gossypium hirsutum L. cv Coker 312 hypocotyl callus were transformed via Agrobacterium tumefaciens with the rice cytochrome P450 gene, CYP81A6 (bel. In rice, bel has been shown to confer resistance to both bentazon and sulfanylurea herbicides. Transformed cells were selected on a liquid medium supplemented alternately or simultaneously with kanamycin (50mg/L and bentazon (4.2 µmol. A total of 17 transgenic cotton lines were recovered, based on the initial resistance to bentazon and on PCR detection of the bel transgene. Bel integration into the cotton genome was confirmed by Southern blot and expression of the transgene was verified by RT-PCR. In greenhouse and experimental plot trials, herbicide (bentazon tolerance of up to 1250 mg/L was demonstrated in the transgenic plants. Transgenic lines with a single copy of the bel gene showed normal Mendelian inheritance of the characteristic. Importantly, resistance to bentazon was shown to be stably incorporated in the T1, T2 and T3 generations of self-fertilised descendents and in plants outcrossed to another upland cotton cultivar. Engineering resistance to bentazon in cotton through the heterologous expression of bel opens the possibility of incorporating this trait into elite cultivars, a strategy that would give growers a more flexible alternative to weed management in cotton crops.

  4. Purification of extensin from cell walls of tomato (hybrid of Lycopersicon esculentum and L. peruvianum) cells in suspension culture.

    Science.gov (United States)

    Brownleader, M D; Dey, P M

    1993-01-01

    Extensin, a hydroxyproline-rich glycoprotein comprising substantial amounts of beta-L-arabinose-hydroxyproline glycosidic linkages is believed to be insolubilized in the cell wall during host-pathogen interaction by a peroxidase/hydroperoxide-mediated cross-linking process. Both extensin precursor and extensin peroxidase were ionically eluted from intact water-washed tomato (hybrid of Lycopersicon esculentum Mill. and L. peruvianum L. (Mill.) cells in suspension cultures and purified to homogeneity by a rapid and simple procedure under mild and non-destructive experimental conditions. The molecular weight of native extensin precursor was estimated to be greater than 240-300 kDa by Superose-12 gel-filtration chromatography. Extensin monomers have previously been designated a molecular weight of approximately 80 kDa. Our results indicate that salt-eluted extensin precursor is not monomeric. Agarose-gel electrophoresis, Superose-12-gel-filtration, extensin-peroxidase-catalysed cross-linking, Mono-S ion-exchange fast protein liquid chromatography (FPLC), and peptide-sequencing data confirmed the homogeneity of the extensin preparation. Evidence that the purified protein was extensin is attributed to the presence of the putative sequence motif--Ser (Hyp)4--within the N-terminal end of the protein. Treatment of extensin with trifluoroacetic acid demonstrated that arabinose was the principal carbohydrate. The amino-acid composition of the purified extensin was similar to those reported in the literature. The cross-linking of extensin in vitro upon incubation with extensin peroxidase and exogenous H2O2 was characteristic of other reported extensins. Furthermore, Mono-S ion-exchange FPLC of native extensin precursor resolved it into two isoforms, A (90%) and B (10%). The amino-acid compositions of extensin A and extensin B were found to be similar to each other and both extensins were cross-linked in vitro by extensin peroxidase.

  5. Enhanced accumulation of phytosterols and phenolic compounds in cyclodextrin-elicited cell suspension culture of Daucus carota.

    Science.gov (United States)

    Miras-Moreno, Begoña; Almagro, Lorena; Pedreño, M A; Sabater-Jara, Ana Belén

    2016-09-01

    In this work, suspension-cultured cells of Daucus carota were used to evaluate the effect of β-cyclodextrins on the production of isoprenoid and phenolic compounds. The results showed that the phytosterols and phenolic compounds were accumulated in the extracellular medium (15100μgL(-1) and 477.46μgL(-1), respectively) in the presence of cyclodextrins. Unlike the phytosterol and phenolic compound content, β-carotene (1138.03μgL(-1)), lutein (25949.54μgL(-1)) and α-tocopherol (8063.82μgL(-1)) chlorophyll a (1625.13μgL(-1)) and b (9.958 (9958.33μgL(-1)) were mainly accumulated inside the cells. Therefore, cyclodextrins were able to induce the cytosolic mevalonate pathway, increasing the biosynthesis of phytosterols and phenolic compounds, and accumulate them outside the cells. However, in the absence of these cyclic oligosaccharidic elicitors, carrot cells mainly accumulated carotenoids through the methylerythritol 4-phosphate pathway. Therefore, the use of cyclodextrins would allow the extracellular accumulation of both phytosterols and phenolic compounds by diverting the carbon flux towards the cytosolic mevalonate/phenylpropanoid pathway. Copyright © 2016 Elsevier Ireland Ltd. All rights reserved.

  6. The age-dependent epigenetic and physiological changes in an Arabidopsis T87 cell suspension culture during long-term cultivation

    International Nuclear Information System (INIS)

    Kwiatkowska, Aleksandra; Zebrowski, Jacek; Oklejewicz, Bernadetta; Czarnik, Justyna; Halibart-Puzio, Joanna; Wnuk, Maciej

    2014-01-01

    Highlights: • A decrease in proliferation rate during long-term cultivation of Arabidopsis cells. • Age-dependent increase in senescence-associated gene expression in Arabidopsis cells. • Age-related increase in DNA methylation, H3K9me2, and H3K27me3 in Arabidopsis cells. • High potential of photosynthetic efficiency of long-term cultured Arabidopsis cells. - Abstract: Plant cell suspension cultures represent good model systems applicable for both basic research and biotechnological purposes. Nevertheless, it is widely known that a prolonged in vitro cultivation of plant cells is associated with genetic and epigenetic instabilities, which may limit the usefulness of plant lines. In this study, the age-dependent epigenetic and physiological changes in an asynchronous Arabidopsis T87 cell culture were examined. A prolonged cultivation period was found to be correlated with a decrease in the proliferation rate and a simultaneous increase in the expression of senescence-associated genes, indicating that the aging process started at the late growth phase of the culture. In addition, increases in the heterochromatin-specific epigenetic markers, i.e., global DNA methylation, H3K9 dimethylation, and H3K27 trimethylation, were observed, suggesting the onset of chromatin condensation, a hallmark of the early stages of plant senescence. Although the number of live cells decreased with an increase in the age of the culture, the remaining viable cells retained a high potential to efficiently perform photosynthesis and did not exhibit any symptoms of photosystem II damage

  7. The age-dependent epigenetic and physiological changes in an Arabidopsis T87 cell suspension culture during long-term cultivation

    Energy Technology Data Exchange (ETDEWEB)

    Kwiatkowska, Aleksandra, E-mail: A.Kwiatkows@gmail.com [Department of Botany, University of Rzeszow, Kolbuszowa (Poland); Zebrowski, Jacek [Department of Plant Physiology, University of Rzeszow, Kolbuszowa (Poland); Oklejewicz, Bernadetta [Department of Genetics, University of Rzeszow, Kolbuszowa (Poland); Czarnik, Justyna [Department of Botany, University of Rzeszow, Kolbuszowa (Poland); Halibart-Puzio, Joanna [Department of Plant Physiology, University of Rzeszow, Kolbuszowa (Poland); Wnuk, Maciej [Department of Genetics, University of Rzeszow, Kolbuszowa (Poland)

    2014-05-02

    Highlights: • A decrease in proliferation rate during long-term cultivation of Arabidopsis cells. • Age-dependent increase in senescence-associated gene expression in Arabidopsis cells. • Age-related increase in DNA methylation, H3K9me2, and H3K27me3 in Arabidopsis cells. • High potential of photosynthetic efficiency of long-term cultured Arabidopsis cells. - Abstract: Plant cell suspension cultures represent good model systems applicable for both basic research and biotechnological purposes. Nevertheless, it is widely known that a prolonged in vitro cultivation of plant cells is associated with genetic and epigenetic instabilities, which may limit the usefulness of plant lines. In this study, the age-dependent epigenetic and physiological changes in an asynchronous Arabidopsis T87 cell culture were examined. A prolonged cultivation period was found to be correlated with a decrease in the proliferation rate and a simultaneous increase in the expression of senescence-associated genes, indicating that the aging process started at the late growth phase of the culture. In addition, increases in the heterochromatin-specific epigenetic markers, i.e., global DNA methylation, H3K9 dimethylation, and H3K27 trimethylation, were observed, suggesting the onset of chromatin condensation, a hallmark of the early stages of plant senescence. Although the number of live cells decreased with an increase in the age of the culture, the remaining viable cells retained a high potential to efficiently perform photosynthesis and did not exhibit any symptoms of photosystem II damage.

  8. Biochemical and morphological responses to abiotc elicitor chitin in suspension-cultured sugarcane cells

    Directory of Open Access Journals (Sweden)

    Maria Izabel Gallão

    2010-04-01

    Full Text Available Cells of Saccharum officinarum submitted to hydrolyzated chitin for 1 to 8h produced phenolic compounds. These alterations were observed through cytochemical methods using Toluidine Blue and Phloroglucinol/HCl. After 4 h, besides cell wall change, there was a change in nuclear pattern of chitin treated cells. There was a 96% increase in nuclear area in 6 h chitin treated material, as observed by Feulgen reaction. The treated cells showed chromatin compacted regions and a degeneration process of nucleoli. In the outer areas of cell wall, there was a polysaccharide desagregation, confirming results obtained for different plants with the use of other elicitors. Peroxidase activity was maximal after 4 h and decreased progressively. PAL activity started to increase at 4 h of incubation. These results showed that chitin hydrolyzate stimulated a defense response in sugarcane cells.Células de Saccharum officinarum quando submetidas a quitina hidrolisada por 1 a 8h produziram material fenólico. Essas alterações foram observadas por meio de métodos citoquímicos como o Azul de Toluidina e Floroglucinol/HCl. Após 4 h, além das mudanças nas paredes celulares houve uma mudança no padrão nuclear das células tratadas com quitina. Por observação da reação de Feulgen, houve um aumento de 96% na área nuclear no material em 6h. Para as células tratadas foram observadas regiões de cromatina compactada e um processo de degeneração do nucléolo. Nas áreas externas da parede celular existia uma desagregação dos polisacarídios confirmando os resultados obtidos para diferentes plantas com o uso de outros elicitores. A atividade da peroxidase foi maxima após 4 h e então decresceu progressivamente. A atividade da PAL aumentou a partir de 4 h de incubação. Estes resultados mostram que o hidrolisado de quitina estimula as respostas de defesa em células de cana.

  9. Glycyrrhiza glabra (Linn.) and Lavandula officinalis (L.) cell suspension cultures-based biotransformation of β-artemether.

    Science.gov (United States)

    Patel, Suman; Gaur, Rashmi; Upadhyaya, Mohita; Mathur, Archana; Mathur, Ajay K; Bhakuni, Rajendra S

    2011-07-01

    The biotransformation of β-artemether (1) by cell suspension cultures of Glycyrrhiza glabra and Lavandula officinalis is reported here for the first time. The major biotransformed product appeared as a grayish-blue color spot on thin-layer chromatography (TLC) with transparent crystal-like texture. Based on its infrared (IR) and (1)H nuclear magnetic resonance (NMR) spectra, the product was characterized as a tetrahydrofuran (THF)-acetate derivative (2). The highest conversion efficiencies of 57 and 60% were obtained when 8-9-day-old cell suspensions of G. glabra and L. officinalis were respectively fed with 4-7 mg of compound 1 in 40 ml of medium per culture and the cells were harvested after 2-5 days of incubation. The addition of compound 1 at the beginning of the culture cycle caused severe growth depression in a dose-dependent manner, resulting in poor bioconversion efficiency of ~25% at 2-5 mg/culture dose only.

  10. Retrobiosynthetic study of salicylic acid in Catharanthus roseus cell suspension cultures

    NARCIS (Netherlands)

    Mustafa, Natali Rianika

    2007-01-01

    Salicylic acid (SA) is an important signal compound in systemic acquired resistance in plants. The level of this C6C1 compound in plants increases after a pathogenic attack. There are two biosynthetic pathways of SA, the phenylalanine pathway, which is thought to occur in plants, and the

  11. Biosynthesis of phenolic compounds inVitis vinifera cell suspension cultures: Study on hydroxycinnamoyl CoA:ligase.

    Science.gov (United States)

    Lotfy, S; Lofty, S; Fleuriet, A; Ramos, T; Macheix, J J

    1989-02-01

    In cell suspensions cultures from grape berry pulp (Vitis vinifera cv. Gamay fréaux)hydroxycinnamoyl CoA ligase (CoAL) displayed maximum activity (100 %) forp-coumaric acid and then, in decreasing order, for ferulic acid (81.3 %) and caffeic acid (60.4 %). No activity was detected with sinapic and cinnamic acids. The changes in CoAL activity during the growth cycle of the culture displayed two peaks : the highest (6 h after subculturing) was linked with a strong increase in protein caused by dilution ; the second was weaker and occurred on the 7th day of culture.Grape cell suspension accumulated mainly peonidin (Pn) and cyanidin (Cy) glucosides (Pn 3-glucoside, Cy 3-glucoside, Pn 3-acetylglucoside, Pn 3-caffeylglucoside, Pn 3-p-coumarylglucoside, and Cy 3-p-coumarylglucoside). Maximum accumulation of anthocyanins was associated with the exponential growth phase of the culture and might be the result of the substantial increase in CoAL activity resulting from the effect of dilution. The second enzyme activity peak was probably oriented towards the acylation of anthocyanins since the percentage of acylated forms increased with time after subculturing.

  12. Detection of anthraquinones and identification of 1,4-naphthohydroquinone in cell suspension cultures of Rudgea jasminoides (Cham.) Müll. Arg. (Rubiaceae)

    OpenAIRE

    Oliveira, Marisa de Cacia; Negri, Giusepina; Salatino, Antônio; Braga, Márcia Regina

    2007-01-01

    In Rubiaceae, anthraquinones and naphthoquinones are secondary metabolites characteristic of the subfamily Rubioideae, in which Rudgea jasminoides is included. Thin-layer chromatography using specific solvent systems and spray reagents indicated the presence of anthraquinones constitutively produced by cell suspension cultures of R. jasminoides. GC/MS analysis detected 1,4-naphthohydroquinone as a product of biosynthesis only after elicitation of the cells with yeast extract (Saccharomyces ce...

  13. Influence of culture medium supplementation of tobacco NT1 cell suspension cultures on the N-glycosylation of human secreted alkaline phosphatase.

    Science.gov (United States)

    Becerra-Arteaga, Alejandro; Shuler, Michael L

    2007-08-15

    We report for the first time that culture conditions, specifically culture medium supplementation with nucleotide-sugar precursors, can alter significantly the N-linked glycosylation of a recombinant protein in plant cell culture. Human secreted alkaline phosphatase produced in tobacco NT1 cell suspension cultures was used as a model system. Plant cell cultures were supplemented with ammonia (30 mM), galactose (1 mM) and glucosamine (10 mM) to improve the extent of N-linked glycosylation. The highest levels of cell density and active extracellular SEAP in supplemented cultures were on average 260 g/L and 0.21 U/mL, respectively, compared to 340 g/L and 0.4 U/mL in unsupplemented cultures. The glycosylation profile of SEAP produced in supplemented cultures was determined via electrospray ionization mass spectrometry with precursor ion scanning and compared to that of SEAP produced in unsupplemented cultures. In supplemented and unsupplemented cultures, two biantennary complex-type structures terminated with one or two N-acetylglucosamines and one paucimannosidic glycan structure comprised about 85% of the SEAP glycan pool. These three structures contained plant-specific xylose and fucose residues and their relative abundances were affected by each supplement. High mannose structures (6-9 mannose residues) accounted for the remaining 15% glycans in all cases. The highest proportion (approximately 66%) of a single complex-type biantennary glycan structure terminated in both antennae by N- acetylglucosamine was obtained with glucosamine supplementation versus only 6% in unsupplemented medium. This structure is amenable for in vitro modification to yield a more human-like glycan and could serve as a route to plant cell culture produced therapeutic glycoproteins. (c) 2007 Wiley Periodicals, Inc.

  14. Effect of sucrose and methyl jasmonate on biomass and anthocyanin production in cell suspension culture of Melastoma malabathricum (Melastomaceae

    Directory of Open Access Journals (Sweden)

    Koay Suan See

    2011-06-01

    Full Text Available Melastoma malabathricum, belongs to the Melastomaceae family, is an important medicinal plant widely distributed from Madagascar to Australia, that is used in traditional remedies for the treatment of variousailments. Besides its medicinal properties, it has been identified as a potential source of anthocyanin production.The present study was carried out to investigate the effect of sucrose and methyl jasmonate and feeding time oncell biomass yield and anthocyanin production in cell suspension culture of M. malabathricum. Addition of differentconcentrations of sucrose into the cell culture of M. malabathricum influenced cell biomass and pigment accumulation. The addition of methyl jasmonate was found to have no effect on cell biomass but the presence of higher amount (12.5-50mg/L had caused a reduction in anthocyanin production and accumulation. MS medium supplemented with 30g/L sucrose and 3.5 mg/L of MeJA added on cero day and 3rd day produced high fresh cell mass at the end of nine days of culture but did not support the production of anthocyanins. However, cells cultured in the medium supplemented with 45g/L sucrose without MeJA showed the highest pigment content (0.69±0.22Cv/g-FCM. The cells cultured in MS medium supplemented with 30 g/L sucrose with 3.5mg/L MeJA added on the 3rd and 6th day of culture, showed the lowest pigment content (0.37-0.40Cv/g-FCM. This study indicated that MeJA was not necessary but sucrose was needed for the enhancement of cell growth and anthocyanin production in M. malabathricum cell cultures. Rev. Biol. Trop. 59 (2: 597-606. Epub 2011 June 01.elastoma malabathricum pertenece a la familia de las melastomáceas, es una planta medicinal importante ampliamente distribuida desde Madagascar hasta Australia, que se utiliza en remedios tradicionales para el tratamiento de diversas dolencias. Además de sus propiedades medicinales, se ha identificado como una fuente potencial de producción de antocianinas. En esta

  15. Membranes replace irradiated blast cells as growth requirement for leukemic blast progenitors in suspension culture

    International Nuclear Information System (INIS)

    Nara, N.; McCulloch, E.A.

    1985-01-01

    The blast cells of acute myeloblastic leukemia (AML) may be considered as a renewal population, maintained by blast stem cells capable of both self-renewal and the generation of progeny with reduced or absent proliferative potential. This growth requires that two conditions be met: first, the cultures must contain growth factors in media conditioned either by phytohemagglutinin (PHA)-stimulated mononuclear leukocytes (PHA-LCM), or by cells of the continuous bladder carcinoma line HTB9 (HTB9-CM). Second, the cell density must be maintained at 10(6) blasts/ml; this may be achieved by adding irradiated cells to smaller numbers of intact blasts. The authors are concerned with the mechanism of the feeding function. They present evidence that (a) cell-cell contact is required. (b) Blasts are heterogeneous in respect to their capacity to support growth. (c) Fractions containing membranes from blast cells will substitute for intact cells in promoting the generation of new blast progenitors in culture. (d) This membrane function may be specific for AML blasts, since membranes from blasts of lymphoblastic leukemia or normal marrow cells were inactive

  16. Do rice suspension-cultured cells treated with abscisic acid mimic developing seeds?

    Science.gov (United States)

    Matsuno, Koya; Fujimura, Tatsuhito

    2015-08-01

    Starch synthesis is activated in the endosperm during seed development and also in rice suspension cells cultured with abscisic acid. In the anticipation that the mechanisms of starch synthesis are similar between the endosperm and the suspension cells cultured with abscisic acid, expression of genes involved in starch synthesis was evaluated in the suspension cells after abscisic acid treatment. However, it was found that the regulatory mechanism of starch synthesis in the suspension cells cultured with abscisic acid was different from that in developing seeds. Expression analyses of genes involved in oil bodies, which accumulate in the embryo and aleurone layer, and seed storage proteins, which accumulate mainly in the endosperm, showed that the former were activated in the suspension cells cultured with abscisic acid, but the latter were not. Master regulators for embryogenesis, OsVP1 (homologue of AtABI3) and OsLFL1 (homologue of AtFUS3 or AtLFL2), were expressed in the suspension cells at levels comparable to those in the embryo. From these results, it is suggested that interactions between regulators and abscisic acid control the synthesis of phytic acid and oil bodies in the cultured cells and embryo. We suggest that the system of suspension cells cultured with abscisic acid helps to reveal the mechanisms of phytic acid and oil body synthesis in embryo.

  17. [Formation of protodioscin and deltoside isomers in suspension cultures of Nepal yam (Dioscorea deltoidea Wall.) cells].

    Science.gov (United States)

    Khandy, M T; Titova, M V; Konstantinova, S V; Kochkin, D V; Ivanov, I M; Nosov, A M

    2016-01-01

    Changes in the content of the furostanol glycosides protodioscin and deltoside, particularly that of the (25S)-isomers of the glycosides, during suspension cultivation of different lines of Nepal yam (Dioscorea deltoidea Wall.) cells of the strain IFR-DM-0.5 has been investigated. The composition of furostanol glycosides has been characterized, and the dynamics of the accumulation of individual glycosides during lengthy subcultivation of cells maintained in flasks or in a barbotage bioreactor has been analyzed. A positive correlation between the growth and accumulation of substances that belonged to the class of furostanol glycosides has been demonstrated for cultured dioscorea cells, whereas the content of some of the individual glycosides varied considerably between the lines of the strain, cultures maintained under different conditions, and even between cells in different phases of the growth cycle. The increased content of (25R)-forms of the glycosides (protodioscin and deltoside) was correlated with a decrease in the cellular growth rate, whereas an increase in culture growth intensity occurred concomitantly to an increase of the amount of (25S)-isomers. This may be indicative of the specific stimulatory effect of (25S)-glycosides, but not the (25R)-forms, on cell proliferation in vitro. Thus, the concentration of (25S)-forms may increase due to the autoselection of cells capable of intensive division during prolonged cultivation.

  18. Establishing in vitro Zinnia elegans cell suspension culture with high tracheary elements differentiation

    NARCIS (Netherlands)

    Twumasi, P.; Schel, J.H.N.; Ieperen, van W.; Woltering, E.J.; Emons, A.M.C.

    2009-01-01

    The Zinnia elegans mesophyll cell culture is a useful system for xylogenesis studies. The system is associated with highly synchronous tracheary element (TE) differentiation, making it more suitable for molecular studies requiring larger amounts of molecular isolates, such as mRNA and proteins and

  19. Effects of 60Co γ-rays irradiation on cell growth and alkaloid accumulation of protocorm-like bodies in suspension cultures from Dendrobium huoshanense

    International Nuclear Information System (INIS)

    Hong Sali; Jin Qing; Huang Bei; Cai Yongping; Lin Yi

    2009-01-01

    Protocorm-like bodies (PLBs) in suspension cultures from Dendrobium huoshanense were irradiated by 60 Co γ-rays at doses of 5, 10, 20 and 30Gy, and alkaloid accumulation of PLBs was studied. The results showed that 60 Co γ-rays irradiation could improve the alkaloid content of PLBs, and the suitable dose was 10Gy. The fresh weight of 10Gy irradiated PLBs was 26.54g/flask, and the alkaloid content was 0.035% on the 36th day. The medium pH and electric conductivity of 10Gy irradiated PLBs changed slightly during the suspension culture period. The results suggested such cultural environment was suitable for PLBs growth continuely. Results also showed that 60 Co γ-rays irradiation could increase the activities of POD, SOD, CAT, PAL and decrease the activity of PPO, these were responsible for the improvement of cell growth and alkaloid accumulation in PLBs. (authors)

  20. Dissection of cis-regulatory element architecture of the rice oleosin gene promoters to assess abscisic acid responsiveness in suspension-cultured rice cells.

    Science.gov (United States)

    Kim, Sol; Lee, Soo-Bin; Han, Chae-Seong; Lim, Mi-Na; Lee, Sung-Eun; Yoon, In Sun; Hwang, Yong-Sic

    2017-08-01

    Oleosins are the most abundant proteins in the monolipid layer surrounding neutral storage lipids that form oil bodies in plants. Several lines of evidence indicate that they are physiologically important for the maintenance of oil body structure and for mobilization of the lipids stored inside. Rice has six oleosin genes in its genome, the expression of all of which was found to be responsive to abscisic acid (ABA) in our examination of mature embryo and aleurone tissues. The 5'-flanking region of OsOle5 was initially characterized for its responsiveness to ABA through a transient expression assay system using the protoplasts from suspension-cultured rice cells. A series of successive deletions and site-directed mutations identified five regions critical for the hormonal induction of its promoter activity. A search for cis-acting elements in these regions deposited in a public database revealed that they contain various promoter elements previously reported to be involved in the ABA response of various genes. A gain-of-function experiment indicated that multiple copies of all five regions were sufficient to provide the minimal promoter with a distinct ABA responsiveness. Comparative sequence analysis of the short, but still ABA-responsive, promoters of OsOle genes revealed no common modular architecture shared by them, indicating that various distinct promoter elements and independent trans-acting factors are involved in the ABA responsiveness of rice oleosin multigenes. Copyright © 2017 Elsevier GmbH. All rights reserved.

  1. In vitro production of azadirachtin from cell suspension cultures of Azadirachta indica.

    Science.gov (United States)

    Sujanya, S; Devi, B Poornasri; Sai, Isha

    2008-03-01

    The present study aimed to elucidate the effect of nutritional alteration on biomass content and azadirachtin production in cell suspensions of the elite neem variety crida-8. Variations in total nitrogen availability in the medium in terms of different ratios of nitrate: ammonium showed that the ratio 4:1 revealed a profound effect, leading to a 1.5-fold increase in the total extracellular azadirachtin production (5.59 mg/l) over the standard MS medium. Reduction in sucrose (15 mg/l) in the medium exhibited a reduction in biomass and absence of azadirachtin, whereas total phosphate reduction raised intracellular azadirachtin production (6.98 mg/l). An altered medium with a nitrate: ammonium ratio of 4:1 coupled with complete elimination of phosphate enhanced biomass by 36% (59.36 g/l).

  2. Nicotine demethylation in Nicotiana cell suspension cultures: N'-formylnornicotine is not involved.

    Science.gov (United States)

    Bartholomeusz, Trixie Ann; Bhogal, Ramneek K; Molinié, Roland; Felpin, François-Xavier; Mathé-Allainmat, Monique; Meier, Anna-Carolin; Dräger, Birgit; Lebreton, Jacques; Roscher, Albrecht; Robins, Richard J; Mesnard, François

    2005-10-01

    Nicotine or nornicotine enriched with stable isotopes in either the N'-methyl group or the pyrrolidine-N were fed to Nicotiana plumbaginifolia suspension cell cultures that do not form endogenous nicotine. The metabolism of these compounds was investigated by analysing the incorporation of isotope into other alkaloids using gas chromatography-mass spectroscopy (GC-MS). Nicotine metabolism primarily resulted in the accumulation of nornicotine, the N'-demethylation product. In addition, six minor metabolites appeared during the course of nicotine metabolism, four of which were identified as cotinine, myosmine, N'-formylnornicotine and N'-carboethoxynornicotine. While cotinine was formed from [(13)C,(2)H(3)-methyl]nicotine without dilution of label, N'-formylnornicotine was labelled at only about 6% of the level of nicotine and N'-carboethoxynornicotine was unlabelled. Feeding with [1'-(15)N]nornicotine resulted in incorporation without dilution of label into both N'-formylnornicotine and N'-carboethoxynornicotine. This pattern strongly indicates that, while nornicotine and cotinine are derived directly from nicotine, N'-formylnornicotine and N'-carboethoxynornicotine are metabolites of nornicotine. Thus, it is directly demonstrated that N'-formylnornicotine is not an intermediate in nicotine demethylation.

  3. The vacuolar transport of aleurain-GFP and 2S albumin-GFP fusions is mediated by the same pre-vacuolar compartments in tobacco BY-2 and Arabidopsis suspension cultured cells.

    Science.gov (United States)

    Miao, Yansong; Li, Kwun Yee; Li, Hong-Ye; Yao, Xiaoqiang; Jiang, Liwen

    2008-12-01

    Soluble proteins reach vacuoles because they contain vacuolar sorting determinants (VSDs) that are recognized by vacuolar sorting receptor (VSR) proteins. Pre-vacuolar compartments (PVCs), defined by VSRs and GFP-VSR reporters in tobacco BY-2 cells, are membrane-bound intermediate organelles that mediate protein traffic from the Golgi apparatus to the vacuole in plant cells. Multiple pathways have been demonstrated to be responsible for vacuolar transport of lytic enzymes and storage proteins to the lytic vacuole (LV) and the protein storage vacuole (PSV), respectively. However, the nature of PVCs for LV and PSV pathways remains unclear. Here, we used two fluorescent reporters, aleurain-GFP and 2S albumin-GFP, that represent traffic of lytic enzymes and storage proteins to LV and PSV, respectively, to study the PVC-mediated transport pathways via transient expression in suspension cultured cells. We demonstrated that the vacuolar transport of aleurain-GFP and 2S albumin-GFP was mediated by the same PVC populations in both tobacco BY-2 and Arabidopsis suspension cultured cells. These PVCs were defined by the seven GFP-AtVSR reporters. In wortmannin-treated cells, the vacuolated PVCs contained the mRFP-AtVSR reporter in their limiting membranes, whereas the soluble aleurain-GFP or 2S albumin-GFP remained in the lumen of the PVCs, indicating a possible in vivo relationship between receptor and cargo within PVCs.

  4. Reprogramming of enteroendocrine K cells to pancreatic β-cells through the combined expression of Nkx6.1 and Neurogenin3, and reaggregation in suspension culture

    Energy Technology Data Exchange (ETDEWEB)

    Lee, Esder; Ryu, Gyeong Ryul; Moon, Sung-Dae; Ko, Seung-Hyun; Ahn, Yu-Bae; Song, Ki-Ho, E-mail: kihos@catholic.ac.kr

    2014-01-17

    Highlights: •K cells were selected from STC-1 cells, a heterogeneous enteroendocrine cell line. •K cells did not express Nkx6.1 and Neurogenin3. •Combined expression of Nkx6.1 and Neurogenin3 reprogrammed K cells to β-cells. •Reprogramming of K cells to β-cells was not complete. -- Abstract: Recent studies have demonstrated that adult cells such as pancreatic exocrine cells can be converted to pancreatic β-cells in a process called cell reprogramming. Enteroendocrine cells and β-cells share similar pathways of differentiation during embryonic development. Notably, enteroendocrine K cells express many of the key proteins found in β-cells. Thus, K cells could be reprogrammed to β-cells under certain conditions. However, there is no clear evidence on whether these cells convert to β-cells. K cells were selected from STC-1 cells, an enteroendocrine cell line expressing multiple hormones. K cells were found to express many genes of transcription factors crucial for islet development and differentiation except for Nkx6.1 and Neurogenin3. A K cell clone stably expressing Nkx6.1 (Nkx6.1{sup +}-K cells) was established. Induction of Neurogenin3 expression in Nkx6.1{sup +}-K cells, by either treatment with a γ-secretase inhibitor or infection with a recombinant adenovirus expressing Neurogenin3, led to a significant increase in Insulin1 mRNA expression. After infection with the adenovirus expressing Neurogenin3 and reaggregation in suspension culture, about 50% of Nkx6.1{sup +}-K cells expressed insulin as determined by immunostaining. The intracellular insulin content was increased markedly. Electron microscopy revealed the presence of insulin granules. However, glucose-stimulated insulin secretion was defective, and there was no glucose lowering effect after transplantation of these cells in diabetic mice. In conclusion, we demonstrated that K cells could be reprogrammed partially to β-cells through the combined expression of Nkx6.1 and Neurogenin3, and

  5. Reprogramming of enteroendocrine K cells to pancreatic β-cells through the combined expression of Nkx6.1 and Neurogenin3, and reaggregation in suspension culture

    International Nuclear Information System (INIS)

    Lee, Esder; Ryu, Gyeong Ryul; Moon, Sung-Dae; Ko, Seung-Hyun; Ahn, Yu-Bae; Song, Ki-Ho

    2014-01-01

    Highlights: •K cells were selected from STC-1 cells, a heterogeneous enteroendocrine cell line. •K cells did not express Nkx6.1 and Neurogenin3. •Combined expression of Nkx6.1 and Neurogenin3 reprogrammed K cells to β-cells. •Reprogramming of K cells to β-cells was not complete. -- Abstract: Recent studies have demonstrated that adult cells such as pancreatic exocrine cells can be converted to pancreatic β-cells in a process called cell reprogramming. Enteroendocrine cells and β-cells share similar pathways of differentiation during embryonic development. Notably, enteroendocrine K cells express many of the key proteins found in β-cells. Thus, K cells could be reprogrammed to β-cells under certain conditions. However, there is no clear evidence on whether these cells convert to β-cells. K cells were selected from STC-1 cells, an enteroendocrine cell line expressing multiple hormones. K cells were found to express many genes of transcription factors crucial for islet development and differentiation except for Nkx6.1 and Neurogenin3. A K cell clone stably expressing Nkx6.1 (Nkx6.1 + -K cells) was established. Induction of Neurogenin3 expression in Nkx6.1 + -K cells, by either treatment with a γ-secretase inhibitor or infection with a recombinant adenovirus expressing Neurogenin3, led to a significant increase in Insulin1 mRNA expression. After infection with the adenovirus expressing Neurogenin3 and reaggregation in suspension culture, about 50% of Nkx6.1 + -K cells expressed insulin as determined by immunostaining. The intracellular insulin content was increased markedly. Electron microscopy revealed the presence of insulin granules. However, glucose-stimulated insulin secretion was defective, and there was no glucose lowering effect after transplantation of these cells in diabetic mice. In conclusion, we demonstrated that K cells could be reprogrammed partially to β-cells through the combined expression of Nkx6.1 and Neurogenin3, and reaggregation

  6. Stable lentiviral transformation of CHO cells for the expression of the hemagglutinin H5 of avian influenza virus in suspension culture

    Directory of Open Access Journals (Sweden)

    Alaín González Pose

    2014-09-01

    Full Text Available Avian influenza virus H5N1 has caused extensive damage worldwide among poultry and humans. Effective expression systems are needed for the production of viral proteins required for monitoring this devastating disease. The present study deals with the establishment of a stable expression system for the hemagglutinin H5 (HAH5 of avian influenza virus using CHO cells in suspension culture transduced with a recombinant lentiviral vector. The synthetic gene coding the HAH5 protein was inserted in a lentiviral vector with the aim of performing a stable transduction of CHO cells. After the selection of recombinant clones, the one with the highest expression level was adapted to suspension culture and the HAH5 protein was purified by immunoaffinity chromatography from the culture supernatant. There were no significant differences when this protein, purified or direct from the culture supernatant of CHO or SiHa cells, was utilized in an immunologic assay using positive and negative sera as reference. It was also demonstrated that the HAH5 protein in its purified form is able to bind anti-HAH5 antibodies generated with proper and non-proper folded proteins. The results demonstrate that the CHO cell line stably transduced with a lentiviral vector coding the sequence of the HAH5 protein and cultured in suspension can be a suitable expression system to obtain this protein for diagnostic purpose in a consistent and reliable manner.

  7. Unexpected features of exponentially growing Tobacco Bright Yellow-2 cell suspension culture in relation to excreted extracellular polysaccharides and cell wall composition.

    Science.gov (United States)

    Issawi, Mohammad; Muhieddine, Mohammad; Girard, Celine; Sol, Vincent; Riou, Catherine

    2017-10-01

    This article presents a new insight about TBY-2 cells; from extracellular polysaccharides secretion to cell wall composition during cell suspension culture. In the medium of cells taken 2 days after dilution (end of lag phase), a two unit pH decrease from 5.38 to 3.45 was observed and linked to a high uronic acid (UA) amount secretion (47.8%) while, in 4 and 7 day-old spent media, pH increased and UA amounts decreased 35.6 and 42.3% UA, respectively. To attain deeper knowledge of the putative link between extracellular polysaccharide excretion and cell wall composition, we determined cell wall UA and neutral sugar composition of cells from D2 to D12 cultures. While cell walls from D2 and D3 cells contained a large amount of uronic acid (twice as much as the other analysed cell walls), similar amounts of neutral sugar were detected in cells from lag to end of exponential phase cells suggesting an enriched pectin network in young cultures. Indeed, monosaccharide composition analysis leads to an estimated percentage of pectins of 56% for D3 cell wall against 45% D7 cell walls indicating that the cells at the mid-exponential growth phase re-organized their cell wall linked to a decrease in secreted UA that finally led to a stabilization of the spent medium pH to 5.4. In conclusion, TBY-2 cell suspension from lag to stationary phase showed cell wall remodeling that could be of interest in drug interaction and internalization study.

  8. Enhanced production of vanillin flavour metabolites by precursor feeding in cell suspension cultures of Decalepis hamiltonii Wight & Arn., in shake flask culture.

    Science.gov (United States)

    Matam, Pradeep; Parvatam, Giridhar; Shetty, Nandini P

    2017-12-01

    The flavour rich tuberous roots of Decalepis hamiltonii are known for its edible and medicinal use and have become endangered due to commercial over-exploitation. Besides 2-Hydroxy-4-methoxy benzaldehyde (2H4MB), other flavour metabolites in tuberous roots include vanillin, 4-Methoxy Cinnamic acid derivatives, aromatic alcohols etc. So far, there are no reports on the pathway of 2H4MB biosynthesis nor there is an organized work on biotransformation using normal and cell suspension cultures for obtaining these metabolites using precursors. The main aim of the study is to develop a method for enhanced production of flavour attributing metabolites through ferulic acid (FA) feeding to the D. hamiltonii callus culture medium. Biomass of D. hamiltonii cell suspension cultures was maximum (200.38 ± 1.56 g/l) by 4th week. Maximum production of 2H4MB was recorded on 4th week (0.08 ± 0.01 mg/100 g dry weight) as quantified by HPLC. Addition of 0.1-1.5 mM ferulic acid as precursor in the culture medium showed significant ( p  vanillin, 2H4MB, vanillic acid, ferulic acid were of 0.1 ± 0.02 mg/100 g, 0.44 ± 0.01 mg/100 g, 0.52 ± 0.04 mg/100 g, 0.18 ± 0.02 mg/100 g DW respectively in 4 weeks of cultured cells supplemented with 1 mM ferulic acid as a precursor. The results indicate that, substantial increase in the levels of flavour metabolites in D. hamiltonii callus suspension culture was achieved. This would be having implications in biosynthesis of respective vanilla flavour attributing metabolites at very high levels for their large scale production.

  9. Sucrose-enhanced biosynthesis of medicinally important antioxidant secondary metabolites in cell suspension cultures of Artemisia absinthium L.

    Science.gov (United States)

    Ali, Mohammad; Abbasi, Bilal Haider; Ahmad, Nisar; Ali, Syed Shujait; Ali, Shahid; Ali, Gul Shad

    2016-12-01

    Natural products are gaining tremendous importance in pharmaceutical industry and attention has been focused on the applications of in vitro technologies to enhance yield and productivity of such products. In this study, we investigated the accumulation of biomass and antioxidant secondary metabolites in response to different carbohydrate sources (sucrose, maltose, fructose and glucose) and sucrose concentrations (1, 3, 5, 7 and 9 %). Moreover, the effects of 3 % repeated sucrose feeding (day-12, -18 and -24) were also investigated. The results showed the superiority of disaccharides over monosaccharides for maximum biomass and secondary metabolites accumulation. Comparable profiles for maximum biomass were observed in response to sucrose and maltose and initial sucrose concentrations of 3 and 5 %. Maximum total phenolic and total flavonoid contents were displayed by cultures treated with sucrose and maltose; however, initial sucrose concentrations of 5 and 7 % were optimum for both classes of metabolites, respectively. Following 3 % extra sucrose feeding, cultures fed on day-24 (late-log phase) showed higher biomass, total phenolic and total flavonoid contents as compared to control cultures. Highest antioxidant activity was exhibited by maltose-treated cultures. Moreover, sucrose-treated cultures displayed positive correlation of antioxidant activity with total phenolics and total flavonoids production. This work describes the stimulatory role of disaccharides and sucrose feeding strategy for higher accumulation of phenolics and flavonoids, which could be potentially scaled up to bioreactor level for the bulk production of these metabolites in suspension cultures of A. absinthium.

  10. Light and Fungal Elicitor Induce 3-Deoxy-d-arabino-Heptulosonate 7-Phosphate Synthase mRNA in Suspension Cultured Cells of Parsley (Petroselinum crispum L.) 1

    Science.gov (United States)

    Henstrand, John M.; McCue, Kent F.; Brink, Kent; Handa, Avtar K.; Herrmann, Klaus M.; Conn, Eric E.

    1992-01-01

    Light and fungal elicitor induce mRNA encoding 3-deoxy-d-arabino-heptulosonate 7-phosphate (DAHP) synthase in suspension cultured cells of parsley (Petroselinum crispum L.). The kinetics and dose response of mRNA accumulation were similar for DAHP synthase and phenylalanine ammonia-lyase (PAL). Six micrograms of elicitor from Phytophthora megasperma f. glycinia gave a detectable induction within 1 hour. Induction of DAHP synthase and PAL mRNAs by light was transient, reaching maximal levels at 4 hours and returning to pretreatment levels after 24 hours. Our data suggest that either light or fungal elicitor transcriptionally activate DAHP synthase. A coordinate regulation for key enzymes in the synthesis of primary and secondary metabolites is indicated. ImagesFigure 1 PMID:16668708

  11. Effects of exogenous growth regulators on cell suspension culture of yin-hong grape (vitis vinifera l.) and establishment of the optimum medium

    International Nuclear Information System (INIS)

    Chao, Y.; Feng, J.C.; Yan, W.Y.; Xiao, Y.; Jun, Y.Y

    2015-01-01

    Callus induced by stem of Yin-hong grape (Vitis vinifera L.) was used as materials and B5 medium as basic medium. The major growth parameters of cell suspension cultures with various levels of 1-Naphthaleneacetic acid (NAA) and 6-Benzyl aminopurine (6-BA) were investigated to provide a basis for the optimum medium of suspension cell cultures of Yin-hong grape regarding cell number, packed cell volume (PCV), dry cell weight (DCW), cell viability, and morphology. All data were analysed by of two-way analysis of variance (ANOVA). Results showed that the treatment of 6-BA and NAA would effect the cell growth dynamics, probably causing logarithmic phase in advance at higher levels of 6-BA. Different concentration of 6-BA and NAA had significant effects on cells number, PCV, DCW and viability (p<0.05), while no-significant effect was observed on the cells morphology. The optimum medium for suspension cell cultures of Yin-hong grape was identified as B5+1.5 mg/L6-BA+1.5 mg/LNAA+ 250 mg/L casein hydrolysate + 30 g/L sucrose. With the optimum medium, the maximum number of suspension cells after the logarithmic growth phase was 34.78 * 108 / mL, the highest cell viability reached 86.45%.; DCW reached 3.84 g/L and PCV reached 0.092 mL/mL after eight days cultivating. (author)

  12. Carbon source dependent somatic embryogenesis and plant regeneration in cotton, Gossypium hirsutum L. cv. SVPR2 through suspension cultures.

    Science.gov (United States)

    Ganesan, M; Jayabalan, N

    2005-10-01

    Highly reproducible and simple protocol for cotton somatic embryogenesis is described here by using different concentrations of maltose, glucose, sucrose and fructose. Maltose (30 g/l) is the best carbon source for embryogenic callus induction and glucose (30 g/l) was suitable for induction, maturation of embryoids and plant regeneration. Creamy white embryogenic calli of hypocotyl explants were formed on medium containing MS basal salts, myo-inositol (100 mg/l), thiamine HCI (0.3 mg/l), picloram (0.3 mg/l), Kin (0.1 mg/l) and maltose (30 g/l). During embryo induction and maturation, accelerated growth was observed in liquid medium containing NH3NO4 (1 g/l), picloram (2.0 mg/l), 2 ip (0.2 mg/l), Kin (0.1 mg/l) and glucose (30 g/l). Before embryoid induction, large clumps of embryogenic tissue were formed. These tissues only produced viable embryoids. Completely matured somatic embryos were germinated successfully on the medium fortified with MS salts, myo-inositol (50 mg/l), thiamine HCl (0.2 mg/l), GA3 (0.2 mg/l), BA (1.0 mg/l) and glucose (30 g/l). Compared with earlier reports, 65% of somatic embryo germination was observed. The abnormal embryo formation was highly reduced by using glucose (30 g/l) compared to other carbon sources. The regenerated plantlets were fertile but smaller in height than the seed derived control plants.

  13. Use of 15N reverse gradient two-dimensional nuclear magnetic resonance spectroscopy to follow metabolic activity in Nicotiana plumbaginifolia cell-suspension cultures.

    Science.gov (United States)

    Mesnard, F; Azaroual, N; Marty, D; Fliniaux, M A; Robins, R J; Vermeersch, G; Monti, J P

    2000-02-01

    Nitrogen metabolism was monitored in suspension cultured cells of Nicotiana plumbaginifolia Viv. using nuclear magnetic resonance (NMR) spectroscopy following the feeding of (15NH4)2SO4 and K15NO3. By using two-dimensional 15N-1H NMR with heteronuclear single-quantum-coherence spectroscopy and heteronuclear multiple-bond-coherence spectroscopy sequences, an enhanced resolution of the incorporation of 15N label into a range of compounds could be detected. Thus, in addition to the amino acids normally observed in one-dimensional 15N NMR (glutamine, aspartate, alanine), several other amino acids could be resolved, notably serine, glycine and proline. Furthermore, it was found that the peak normally assigned to the non-protein amino-acid gamma-aminobutyric acid in the one-dimensional 15N NMR spectrum was resolved into a several components. A peak of N-acetylated compounds was resolved, probably composed of the intermediates in arginine biosynthesis, N-acetylglutamate and N-acetylornithine and, possibly, the intermediate of putrescine degradation into gamma-aminobutyric acid, N-acetylputrescine. The occurrence of 15N-label in agmatine and the low detection of labelled putrescine indicate that crucial intermediates of the pathway from glutamate to polyamines and/or the tobacco alkaloids could be monitored. For the first time, labelling of the peptide glutathione and of the nucleotide uridine could be seen.

  14. Human adipose stem cells maintain proliferative, synthetic and multipotential properties when suspension cultured as self-assembling spheroids

    International Nuclear Information System (INIS)

    Kapur, S K; Wang, X; Shang, H; Yun, S; Li, X; Feng, G; Khurgel, M; Katz, A J

    2012-01-01

    Adipose-derived stromal/stem cells (ASCs) have been gaining recognition as an extremely versatile cell source for tissue engineering. The usefulness of ASCs in biofabrication is further enhanced by our demonstration of the unique properties of these cells when they are cultured as three-dimensional cellular aggregates or spheroids. As described herein, three-dimensional formulations, or self-assembling ASC spheroids develop their own extracellular matrix that serves to increase the robustness of the cells to mechanical stresses. The composition of the extracellular matrix can be altered based on the external environment of the spheroids and these constructs can be grown in a reproducible manner and to a consistent size. The spheroid formulation helps preserve the viability and developmental plasticity of ASCs even under defined, serum-free media conditions. For the first time, we show that multiple generations of adherent ASCs produced from these spheroids retain their ability to differentiate into multiple cell/tissue types. These demonstrated properties support the idea that culture-expanded ASCs are an excellent candidate cellular material for ‘organ printing’—the approach of developing complex tissue structures from a standardized cell ‘ink’ or cell formulation. (paper)

  15. The necrotroph Botrytis cinerea induces a non-host type II resistance mechanism in Pinus pinaster suspension-cultured cells.

    Science.gov (United States)

    Azevedo, Herlânder; Lino-Neto, Teresa; Tavares, Rui Manuel

    2008-03-01

    Models of non-host resistance have failed to account for the pathogenicity of necrotrophic agents. During the interaction of Pinus pinaster (maritime pine) with the non-host necrotrophic pathogen Botrytis cinerea, the generation and scavenging of reactive oxygen species (ROS) and the induction of the hypersensitive response (HR) were analyzed. Elicitation of maritime pine suspended cells with B. cinerea spores resulted in the biphasic induction of ROS. The phase I oxidative burst was dependent on calcium influx, while the phase II oxidative burst also depended on NADPH oxidase, protein kinase activity, and de novo transcription and protein synthesis. A decline was observed in catalase (CAT) and superoxide dismutase (SOD) activity, together with the down-regulation of Fe-Sod1, chlCu, Zn-Sod1 and csApx1, suggesting a coordinated response towards a decrease in the ROS-scavenging capacity of maritime pine cells during challenge. Following the second oxidative burst, programmed cell death events characteristic of the HR were observed. The results suggest the ROS-mediated and cell-breach-independent activation of Type II non-host resistance during the P. pinaster-B. cinerea interaction.

  16. Evidence for the involvement of tetrahydrofolate in the demethylation of nicotine by Nicotiana plumbaginifolia cell-suspension cultures.

    Science.gov (United States)

    Mesnard, François; Roscher, Albrecht; Garlick, Andrew P; Girard, Sandrine; Baguet, Evelyne; Arroo, Randolf R J; Lebreton, Jacques; Robins, Richard J; Ratcliffe, GeorgeR

    2002-04-01

    The conversion of nicotine to nornicotine by Nicotiana plumbaginifolia Viv. cells was investigated by analysing the redistribution of label during feeding experiments with (R,S)-[2H- methyl]nicotine, (R,S)-[13C- methyl]nicotine and (R,S)-[14C- methyl]nicotine, and the results show that the N-methyl group of nicotine can be recycled into primary metabolism. Nuclear magnetic resonance (NMR) analysis of ethanolic extracts of cells grown in the presence of (R,S)-[13C- methyl]nicotine, using 1H-13C correlation spectroscopy (HMQC, HMBC), revealed the presence of [3-13C]serine and [13C- methyl]methionine. Label was also identified in a cysteinyl derivative and in several methoxylated compounds, but no evidence was obtained with either NMR or ion-trap mass spectrometry for the presence of any intermediate between nicotine and nornicotine. However, experiments with (R,S)-[14C- methyl]nicotine indicated that 70-75% of the metabolised label was released as carbon dioxide. These results are consistent with a pathway in which the oxidative hydrolysis of the nicotine methyl produces an unstable intermediate, N'-hydroxymethylnornicotine, that breaks down spontaneously to nornicotine and formaldehyde, with the formaldehyde being metabolised either directly to formate and carbon dioxide, or through the tetrahydrofolate-mediated pathways of one-carbon metabolism. However since the key intermediate, N-hydroxymethylnornicotine, could not be detected, the possibility of a direct methyl group transfer to tetrahydrofolate cannot be excluded.

  17. Sucrose metabolizing enzymes in cell suspension cultures of Bauhinia forficata, Curcuma zedoaria and Phaseolus vulgaris Enzimas do metabolismo da sacarose em cultura celular de Bauhinia forficata, Curcuma zedoaria e Phaseolus vulgaris

    Directory of Open Access Journals (Sweden)

    Marcia Ometto de Mello

    2001-09-01

    Full Text Available The objective of this work was to study the activity of sucrose metabolizing enzymes in extracts of cell suspension cultures of Bauhinia forficata Link, Curcuma zedoaria Roscoe and Phaseolus vulgaris L. Invertase pathway was identified in the three studied species. Sucrose synthase pathway was also responsible for sucrose metabolism in Curcuma zedoaria and Phaseolus vulgaris cells. Activity values higher than 300 nmol min-1 mg-1 of protein were found for acid and neutral invertases, UDPglucose pyrophosphorylase and phosphoglucomutase in the cell extract of the three plant species. Sucrose synthase showed low activity in Bauhinia forficata cells. As sucrose concentration in the culture medium decreased, sucrose synthase activity increased in C. zedoaria and P. vulgaris cells. The glycolytic enzymes activity gradually reduced at the end of the culture period, when carbohydrate was limited.O objetivo deste trabalho foi estudar as enzimas do metabolismo da sacarose em culturas de célula em suspensão de Bauhinia forficata Link, Curcuma zedoaria Roscoe e Phaseolus vulgaris L. A via da invertase foi identificada nas três espécies estudadas. A via da sacarose sintase também foi responsável pelo metabolismo da sacarose em células de Curcuma zedoaria e Phaseolus vulgaris. Foram encontradas atividades maiores que 300 nmol min-1 mg-1 de proteína das enzimas invertase ácida e alcalina, UDPglicose pirofosforilase e fosfoglicomutase no extrato celular das três espécies de plantas. A sacarose sintase mostrou atividade baixa nas células de Bauhinia forficata. À medida que a concentração de sacarose no meio de cultura diminuiu, a atividade da sacarose sintase aumentou em células de Curcuma zedoaria e Phaseolus vulgaris. Ao final do período de cultura, quando os carboidratos se tornaram limitantes, as atividades das enzimas glicolíticas reduziram-se gradualmente.

  18. Physiological responses of suspension cultures of Catharanthus roseus to aluminum: changes in polyamines and inorganic ions

    Science.gov (United States)

    Xinhua Zhou; Rakesh Minocha; Subhash C. Minocha

    1995-01-01

    The effects of aluminum (Al) treatment on polyamines were studied using suspension cultures of Madagascar periwinkle [Catharanthus roseus (L.) G. Don]. The addition of A1 (0.2, 0.5, 1.0 mM) to the suspension cultures caused a significant increase in putrescine within 24h only in freshly transferred cells. By contrast, Al treatment reduced putrescine...

  19. Estrogen response of MCF-7 cells grown on diverse substrates and in suspension culture: promotion of morphological heterogeneity, modulation of progestin receptor induction; cell-substrate interactions on collagen gels.

    Science.gov (United States)

    Pourreau-Schneider, N; Berthois, Y; Mittre, H; Charpin, C; Jacquemier, J; Martin, P M

    1984-12-01

    In this study we observed the incidence of hormone sensitivity in the response of MCF-7 cells to estrogen stimulation when the cells were cultured in different contact environments (hydrophilic plastic, bovine corneal extracellular matrix, type I collagen and in suspension culture). The major purpose was to describe the influence of cell to cell and cell to substrate contacts on the morphological response to estrogen treatment. However, other parameters including growth and induction of progestin receptor were also explored, keeping in mind that the MCF-7 cell line, although representative of normal mammary epithelium in that it contains a similar hormone receptivity, was selected in vitro from a metastatic population in a pleural effusion. Although substrate conditions did not modify growth enhancement by estrogens, progestin receptor levels were significantly higher in three-dimensional spheroid cultures in which cell to cell contacts were optimal due to elimination of basal contact. A careful morphological survey of large surfaces lead to an objective opinion of the overall effect of the hormone treatment on the non-cloned cell line in which a marked heterogeneity in the response of individual cells was observed. In terms of morphofunctional differentiation, the edification of acini with dense microvillus coating was best in suspension culture. When sections were made perpendicular to the plane of cultures on collagen gel rafts two other phenomena were noted: decrease in intercellular junctions, resulting in reduced cell to cell cohesion, and accumulation biodegradation products in the collagen lattice. This suggested a hormone-mediated interaction between the metastatic cells and the fibrillar substrate, collagen I, one of the major constituents of tissue stroma. This estrogen response might be related to the metastatic phenotype and must be distinct from their hormone sensitivity in terms of growth and differentiation since hormone receptivity is generally

  20. In vitro morphogenesis and cell suspension culture establishment in Piper solmsianum C. DC. (Piperaceae Morfogênese in vitro e estabelecimento de culturas de suspensão celular em Piper solmsianum C. DC. (Piperaceae

    Directory of Open Access Journals (Sweden)

    Tiago Santana Balbuena

    2009-03-01

    Full Text Available Piper solmsianum is a shrub from Southeast Brazil in which many biologically active compounds were identified. The aim of this work was to establish a cell suspension culture system for this species. With this in mind, petiole and leaf explants obtained from in vitro plantlets were cultured in the presence of different plant growth regulator combinations (IAA, NAA, 2,4-D and BA. Root and indirect shoot adventitious formation, detected by histological analysis, was observed. Besides the different combinations of plant growth regulators, light regime and the supplement of activated charcoal (1.5 mg.l-1 were tested for callus induction and growth. Cultures maintained in light, on a 0.2 mg.l-1 2,4-D and 2 mg.l-1 BA supplemented medium, and in the absence of activated charcoal, showed the highest calli fresh matter increment. From a callus culture, cell suspension cultures were established and their growth and metabolite accumulation studied. The achieved results may be useful for further characterization of the activated secondary metabolites pathways in in vitro systems of P. solmsianum.Piper solmsianum é uma espécie herbácea do sudeste brasileiro onde vários compostos biologicamente ativos já foram identificados. O objetivo deste trabalho foi estabelecer suspensões celulares nesta espécie. Para tanto, foram utilizados explantes de pecíolos e folhas, retirados de plântulas cultivadas in vitro, os quais foram submetidos a diferentes combinações de reguladores de crescimento (AIA, ANA, 2,4-D e BAP. Foi obtida a neo-formação de raízes e brotos, estes últimos através do processo de organogênese indireta evidenciada por estudos histológicos. Para a indução e crescimento dos calos, foram avaliados, além das diferentes combinações de reguladores de crescimento, a suplementação ao meio de cultura de carvão ativado (1,5 mg.l-1 e o regime de luz. Culturas mantidas na luz, em meio de cultura suplementado com 0,2 mg.l-1 2,4-D e 2 mg

  1. Rotary orbital suspension culture of embryonic stem cell-derived neural stem/progenitor cells: impact of hydrodynamic culture on aggregate yield, morphology and cell phenotype.

    Science.gov (United States)

    Laundos, Tiago L; Silva, Joana; Assunção, Marisa; Quelhas, Pedro; Monteiro, Cátia; Oliveira, Carla; Oliveira, Maria J; Pêgo, Ana P; Amaral, Isabel F

    2017-08-01

    Embryonic stem (ES)-derived neural stem/progenitor cells (ES-NSPCs) constitute a promising cell source for application in cell therapies for the treatment of central nervous system disorders. In this study, a rotary orbital hydrodynamic culture system was applied to single-cell suspensions of ES-NSPCs, to obtain homogeneously-sized ES-NSPC cellular aggregates (neurospheres). Hydrodynamic culture allowed the formation of ES-NSPC neurospheres with a narrower size distribution than statically cultured neurospheres, increasing orbital speeds leading to smaller-sized neurospheres and higher neurosphere yield. Neurospheres formed under hydrodynamic conditions (72 h at 55 rpm) showed higher cell compaction and comparable percentages of viable, dead, apoptotic and proliferative cells. Further characterization of cellular aggregates provided new insights into the effect of hydrodynamic shear on ES-NSPC behaviour. Rotary neurospheres exhibited reduced protein levels of N-cadherin and β-catenin, and higher deposition of laminin (without impacting fibronectin deposition), matrix metalloproteinase-2 (MMP-2) activity and percentage of neuronal cells. In line with the increased MMP-2 activity levels found, hydrodynamically-cultured neurospheres showed higher outward migration on laminin. Moreover, when cultured in a 3D fibrin hydrogel, rotary neurospheres generated an increased percentage of neuronal cells. In conclusion, the application of a constant orbital speed to single-cell suspensions of ES-NSPCs, besides allowing the formation of homogeneously-sized neurospheres, promoted ES-NSPC differentiation and outward migration, possibly by influencing the expression of cell-cell adhesion molecules and the secretion of proteases/extracellular matrix proteins. These findings are important when establishing the culture conditions needed to obtain uniformly-sized ES-NSPC aggregates, either for use in regenerative therapies or in in vitro platforms for biomaterial development or

  2. Effects of gamma irradiation on the plasma membrane of suspension-cultured apple cells. Rapid irreversible inhibition of H+-ATPase activity

    International Nuclear Information System (INIS)

    Dong, C.-Z.; Montillet, J.-L.; Triantaphylides, C.

    1994-01-01

    The effects of ionizing radiation, used in post-harvest treatment of fruit and vegetables. were investigated on cultured apple cells (Pyrus malus L. cv. Royal Red) on a short-term period. Irradiation (2 kGy) induced an increase of passive ion effluxes from cells and a decrease of cell capacity to regulate external pH. These alterations are likely due to effects on plasma membrane structure and function and were further investigated by studying the effects of irradiation on plasma membrane H + -ATPase activity. Plasma membrane-enriched vesicles were prepared and the H + -ATPase activity was characterized. Irradiation of the vesicles induced a dose dependent inhibition of H + -ATPase activity. The loss of enzyme activity was immediate, even at low doses (0.5 kGy), and was not reversed by the addition of 2mM dithiothreitol. This inhibition may be the result of an irreversible oxidation of enzyme sulfhydryl moieties and/or the result of changes induced within the lipid bilayer affecting the membrane-enzyme interactions. Further analysis of the H + -ATPase activity was carried out on vesicles obtained from irradiated cells confirming the previous results. In vivo recovery of activity was not observed within 5 h following the treatment, thus explaining the decrease of cell capacity to regulate external pH. This rapid irreversible inhibition of the plasma membrane H + -ATPase must be considered as one of the most important primary biochemical events occurring in irradiated plant material. (author)

  3. Identification of Alternaria alternata Mycotoxins by LC-SPE-NMR and Their Cytotoxic Effects to Soybean (Glycine max Cell Suspension Culture

    Directory of Open Access Journals (Sweden)

    Edson Rodrigues-Filho

    2013-02-01

    Full Text Available This present work describes the application of liquid chromatograpy-solid phase extraction-nuclear magnetic resonance spectroscopy to analyse Alternaria alternata crude extracts. Altenusin (1, alternariol (2, 3'-hydroxyalternariol monomethyl ether (3, and alternariol monomethyl ether (4, were separated and identified. High-resolution mass spectrometry confirmed the proposed structures. The cytotoxic effects of these compounds towards plants were determined using soybean (Glycine max cell cultures as a model. EC50 values which range from 0.11 (±0.02 to 4.69 (±0.47 μM showed the high cytotoxicity of these compounds.

  4. Elicitation of andrographolide in the suspension cultures of Andrographis paniculata.

    Science.gov (United States)

    Gandi, Suryakala; Rao, Kiranmayee; Chodisetti, Bhuvaneswari; Giri, Archana

    2012-12-01

    Andrographis paniculata belonging to the family Acanthaceae produces a group of diterpene lactones, one of which is the pharmaceutically important-andrographolide. It is known to possess various important biological properties like anticancer, anti-HIV, anti-inflammatory, etc. This is the first report on the production of andrographolide in the cell suspension cultures of Andrographis paniculata by 'elicitation'. Elicitation was attempted to enhance the andrographolide content in the suspension cultures of Andrographis paniculata and also to ascertain its stimulation under stress conditions or in response to pathogen attack. The maximum andrographolide production was found to be 1.53 mg/g dry cell weight (DCW) at the end of stationary phase during the growth curve. The biotic elicitors (yeast, Escherichia coli, Bacillus subtilis, Agrobacterium rhizogenes 532 and Agrobacterium tumefaciens C 58) were more effective in eliciting the response when compared to the abiotic elicitors (CdCl(2), AgNO(3), CuCl(2) and HgCl(2)). Yeast has shown to stimulate maximum accumulation of 13.5 mg/g DCW andrographolide, which was found to be 8.82-fold higher than the untreated cultures.

  5. Growth of Bauhinia forficata Link, Curcuma zedoaria Roscoe and Phaseolus vulgaris L. cell suspension cultures with carbon sources Crescimento de cultura de células em suspensão de Bauhinia forficata Link, Curcuma zedoaria Roscoe e Phaseolus vulgaris L. em fontes de carbono

    Directory of Open Access Journals (Sweden)

    Marcia Ometto Mello

    2001-09-01

    Full Text Available Cell suspension cultures of Bauhinia forficata Link, Curcuma zedoaria Roscoe and Phaseolus vulgaris L. were used to test plant ability to utilize an alternative to sucrose as carbon source and energy for growth. Glycerol, sorbitol and galactose were the alternative carbon sources tested. Cell suspension cultures established on liquid medium containing sucrose were transferred to culture medium supplemented with sucrose or glycerol, or sorbitol, or galactose as the sole carbon source. Fresh and dry weight increasing and protein content showed marked differences among the different carbon sources used. Sucrose was the best carbon source for all the three plant species tested. Galactose and glycerol promoted slow or no growth of the three studied species. Sucrose in liquid medium promoted initiation of meristemoid formation. Sorbitol, which was ineffective on promoting significant growth, was the only alternative carbon source tested that also promoted this effect.Culturas de células em suspensão de Bauhinia forficata Link, Curcuma zedoaria Roscoe e Phaseolus vulgaris L. foram usadas para avaliar a eficiência de fontes alternativas de carbono e energia. Glicerol, sorbitol e galactose foram as fontes alternativas estudadas. As culturas de células estabelecidas em meio líquido contendo sacarose foram transferidas para meios de cultura suplementados com sacarose ou glicerol ou sorbitol ou galactose. A fonte de carbono afetou distintamente os ganhos de matéria fresca, matéria seca e o acúmulo de proteína. A sacarose foi a melhor fonte de carbono para as três espécies estudadas. Galactose e glicerol promoveram pequeno crescimento das três espécies estudadas. A sacarose utilizada como fonte de carbono no meio líquido, promoveu o início de organização celular conhecido como a formação de meristemóides. Sorbitol, que não promoveu crescimento significativo, foi a única fonte alternativa de carbono testada que também promoveu este

  6. Effects of chilling on protein synthesis in tomato suspension cultures

    International Nuclear Information System (INIS)

    Matadial, B.; Pauls, K.P.

    1989-01-01

    The effect of chilling on cell growth, cell viability, protein content and protein composition in suspension cultures of L. esculentum and L. hirsutum was investigated. Cell growth for both species was arrested at 2 degrees C but when cultures were transferred to 25 degree C cell growth resumed. There was no difference in viability between control and chilled cultures of L. esculentum, however, L. hirsutum control cultures exhibited larger amounts of Fluorescein Diacetate induced fluorescence than chilled cultures. 35 S-methionine incorporation into proteins was 2.5-2 times higher in L. hirsutum than in L. esculentum. Quantitative and qualitative differences, in 35 S-methionine labelled proteins, between chilled and control cultures were observed by SDS-PAGE and fluorography. Protein content in chilled cultures decreased over time but then increased when cultures were transferred to 25 degrees C

  7. Production of secondary metabolites trimethyl xanthina by Camellia sinensis L suspension culture

    Science.gov (United States)

    Sutini, Sodiq, Mochamad; Muslihatin, Wirdhatul; Indra, Mochamad Rasjad

    2017-06-01

    Bioactive trimethyl xanthina can be obtained from the plant Camellia sinensis L. To obtain bioactive plant of which there are several hurdles for instance to wait up to five years to be harvested, also it needs land at a certain height from the sea level. Therefore, the production of secondary metabolites trimethyl xanthina need to be developed with suspense culture techniques. The purpose of this study obtained the production of bioactive trimethyl xanthina way culturally suspense in large scale with a relatively short time, potentially as anti-oxidants. Research methods include: (1) initiation of callus from pieces of leaves, shoots the youngest of the plant Camellia sinensis L in the media MS with the optimization of the addition of growth regulators, (2) the subculture of callus on media and plant growth regulator that is equal to the stage of initiation, (3) initiation of suspension culture using explants of callus Camellia sinensis L, (4) Analysis of secondary metabolites trimethyl xanthina growth in suspension culture, (5) the isolation and identification of trimethyl xanthina qualitatively and quantitatively using thin layer chromatography/high performance chromatography column. The results of the study suspension cultures containing bioactive trimethyl xanthina candidates that can be used as an antioxidant.

  8. Cell division arrest by gamma-irradiation in photoautotrophic suspension culture of Euphorbia characias: maintenance of photosynthetic capacity and overaccumulation of sucrose

    International Nuclear Information System (INIS)

    Chagvardieff, P.; Dimon, B.; Carrier, P.; Triantaphylides, C.

    1989-01-01

    Gamma-irradiation (250 Gy) applied to photoautotrophic cell suspensions of Euphorbia characias L. in the exponential growth phase led to the arrest of cell division and to a subsequent overaccumulation of sucrose and dry matter. From the fourth day of culture, the chlorophyll content and gross photosynthesis were not depressed by gamma-treatment nor by sugar accumulation. In both cultures, no difference was observed between oxygen uptake in the light at CO 2 saturating concentration and in the dark, suggesting that no change in energy-dissipative reactions took place after irradiation. A slight increase in oxygen uptake in both light and dark was observed in irradiated cells during the first four days. However, in the absence of limiting factors, the photosynthetic capacities of the dividing and irradiated non-dividing photoautotrophic cells were identical but higher than that of the non-dividing cells in the stationary growth phase. This suggests that gamma-irradiation arrests cell division by a mechanism different to that occurring in stationary-phase cultures. This may be of value in investigating the metabolism of secondary products. (author)

  9. Generation of functional cardiomyocytes from rat embryonic and induced pluripotent stem cells using feeder-free expansion and differentiation in suspension culture.

    Science.gov (United States)

    Dahlmann, Julia; Awad, George; Dolny, Carsten; Weinert, Sönke; Richter, Karin; Fischer, Klaus-Dieter; Munsch, Thomas; Leßmann, Volkmar; Volleth, Marianne; Zenker, Martin; Chen, Yaoyao; Merkl, Claudia; Schnieke, Angelika; Baraki, Hassina; Kutschka, Ingo; Kensah, George

    2018-01-01

    The possibility to generate cardiomyocytes from pluripotent stem cells in vitro has enormous significance for basic research, disease modeling, drug development and heart repair. The concept of heart muscle reconstruction has been studied and optimized in the rat model using rat primary cardiovascular cells or xenogeneic pluripotent stem cell derived-cardiomyocytes for years. However, the lack of rat pluripotent stem cells (rPSCs) and their cardiovascular derivatives prevented the establishment of an authentic clinically relevant syngeneic or allogeneic rat heart regeneration model. In this study, we comparatively explored the potential of recently available rat embryonic stem cells (rESCs) and induced pluripotent stem cells (riPSCs) as a source for cardiomyocytes (CMs). We developed feeder cell-free culture conditions facilitating the expansion of undifferentiated rPSCs and initiated cardiac differentiation by embryoid body (EB)-formation in agarose microwell arrays, which substituted the robust but labor-intensive hanging drop (HD) method. Ascorbic acid was identified as an efficient enhancer of cardiac differentiation in both rPSC types by significantly increasing the number of beating EBs (3.6 ± 1.6-fold for rESCs and 17.6 ± 3.2-fold for riPSCs). These optimizations resulted in a differentiation efficiency of up to 20% cTnTpos rPSC-derived CMs. CMs showed spontaneous contractions, expressed cardiac markers and had typical morphological features. Electrophysiology of riPSC-CMs revealed different cardiac subtypes and physiological responses to cardio-active drugs. In conclusion, we describe rPSCs as a robust source of CMs, which is a prerequisite for detailed preclinical studies of myocardial reconstruction in a physiologically and immunologically relevant small animal model.

  10. Visualization of phosphatidylinositol 4,5-bisphosphate in the plasma membrane of suspension-cultured tobacco BY-2 cells and whole Arabidopsis seedlings

    NARCIS (Netherlands)

    Leeuwen, van W.; Vermeer, J.E.M.; Gadella, T.W.J.; Munnik, T.

    2007-01-01

    Phosphatidylinositol 4,5-bisphosphate [PtdIns(4,5)P-2] is an important signalling lipid in mammalian cells, where it functions as a second-messenger precursor in response to agonist-dependent activation of phospholipase C (PLC) but also operates as a signalling molecule on its own. Much of the

  11. Actin and myosin regulate cytoplasm stiffness in plant cells: a study using optical tweezers

    NARCIS (Netherlands)

    Honing, van der H.S.; Ruijter, de N.C.A.; Emons, A.M.C.; Ketelaar, T.

    2010-01-01

    Here, we produced cytoplasmic protrusions with optical tweezers in mature BY-2 suspension cultured cells to study the parameters involved in the movement of actin filaments during changes in cytoplasmic organization and to determine whether stiffness is an actin-related property of plant cytoplasm.

  12. The influence of fast neutron irradiation through micropropagation, calli induction and cell aggregate suspension culture of tapak dara cultivate vinca rosea linn

    International Nuclear Information System (INIS)

    Wahid, Rosmiarty A.

    2000-01-01

    Study on the influence of fast neutron irradiation toward tissue induction of apical shoot, calli of leaf and corolla as well as development of bud micropropagation using variety of MS and Gamborg (B5) which were supplemented with growth hormone 2,4-D NAA, BAP and kinetin has been carried out. Cell aggregates were obtained from modified liquid media by mixing MS macro element and Gamborg vitamin. Influence of the iow level irradiation (0,5-10 Gy) was investigated for auxiliary bud micropropagation , middle (5 - 20 Gy) for calli induction, while for call aggregates higher doses (until 30 Gy) were used. Optimum growth of bud micropropagation was stimulate at dose range between 0,5-1Gy and grown on MS supplemented whit BAP and NAAN, while for leaf and corolla calli was at 5 Gy, on MS media which was supplemented whit 1 mg/L kinetin, 10mg/L BAP and 0,5 mg/L NAA. However, neutron dose of 10 Gy decreased the induction of leaf and corolla calli. The highest radioresistance was shown by cell aggregates of leaf calli that grew prosperously up to 20Gy. Key words : fast neutron, micropropagation, tissue culture, cell culture, vinca rosea L

  13. Establecimiento de un cultivo de celulas en suspensión de Eucalyptus cinérea Establishment of cell suspension culture of Eucalyptus cinerea

    Directory of Open Access Journals (Sweden)

    Arias Zabala Mario

    2002-06-01

    Full Text Available Se desarrolla un protocolo para la obtención y establecimiento de suspensiones celulares de E. cinerea. La concentración de las hormonas 2,4 D Y BAP tienen un efecto significativo en la formación de callos friables de E. cinerea, obteniendo una respuesta periódica en la formación de callos friables con respecto a la concentración de las hormonas. Puede obtenerse hasta un 90% de formación de callos friables con varias combinaciones hormonales; primero, con concentraciones alrededor de 3,0 mg/L de 2,4 D Y 1,0 mg/L de BAp, y segundo, alrededor de 6,0 mg/L de 2,4 D Y1,0 mg/L de BAP. A partir de los callos anteriores, se obtienen suspensiones celulares con un activo crecimiento celular, con tiempos de duplicación entre cuatro y siete días, y alcanzando densidades celulares de 15 g células secas/L. Las suspensiones de E. cinerea ofrecen una herramienta importante para la propagación de esta especie vía embriogénesis somática, estudio de biorreactores, producción de metabolitos secundarios y procesos de biotransformación.A protocol is developed for obtaining and establishment of E. cinerea cell suspension. The concentration of hormones 2,4 D and BAP have a significant effect in the formation of friable callus of E. cinerea, obtaining a periodic answer in the formation of friable callus with regard to hormones concentration. It can be obtained until 90% of formation of friable callus in several hormone combinations, first with concentrations around 3,0 mg/L of 2,4 D and 1,0 mg/L of BAP; and second, around 6,0 mgIL of 2,4 D and 1,0 mg/L of BAP. Using the last callus, cell suspensions are obtained with an active cellular growth, with times of duplication between 4 and 7 days and obtaining cell densities of 15 g of dry cells/L. The suspensions of E. cinerea offer an important tool for the propagation of this specie by somatic embryogenesis, bioreactors study, production of secondary metabolites and biotransformation processes.

  14. Analysis of redox relationships in the plant cell cycle: determinations of ascorbate, glutathione and poly (ADPribose)polymerase (PARP) in plant cell cultures.

    Science.gov (United States)

    Foyer, Christine H; Pellny, Till K; Locato, Vittoria; De Gara, Laura

    2008-01-01

    Reactive oxygen species (ROS) and low molecular weight antioxidants, such as glutathione and ascorbate, are powerful signaling molecules that participate in the control of plant growth and development, and modulate progression through the mitotic cell cycle. Enhanced reactive oxygen species accumulation or low levels of ascorbate or glutathione cause the cell cycle to arrest and halt progression especially through the G1 checkpoint. Plant cell suspension cultures have proved to be particularly useful tools for the study of cell cycle regulation. Here we provide effective and accurate methods for the measurement of changes in the cellular ascorbate and glutathione pools and the activities of related enzymes such poly (ADP-ribose) polymerase during mitosis and cell expansion, particularly in cell suspension cultures. These methods can be used in studies seeking to improve current understanding of the roles of redox controls on cell division and cell expansion.

  15. Callus and cell suspension cultures of carnation

    DEFF Research Database (Denmark)

    Engvild, Kjeld Christensen

    1972-01-01

    Callus cultures of carnation, Dianthus caryophyllus L. ev. G. J. Sim, were grown on a synthetic medium of half strength Murashige and Skoog salts, 3 % sucrose, 100 mg/l of myo-inositol, 0.5 mg/l each of thiamin, HCl, pyridoxin, HCl and nicotinic acid and 10 g/l agar. Optimal concentrations...

  16. Sugar transport by maize endosperm suspension cultures

    International Nuclear Information System (INIS)

    Felker, F.C.; Goodwin, J.C.

    1987-01-01

    To determine the mechanism of sugar uptake by suspension cultures derived from developing maize (Zea mays L.) endosperm, incorporation of radioactivity from 14 C-sugars by the tissue in the mid-log phase of growth was examined. Among the sugars tested was l'-deoxy-l'-fluorosucrose (FS), a derivative not hydrolyzed by invertase but recognized by sucrose carriers in other systems. At 40 mM, uptake of label from FS was 23% of that from sucrose, while uptake of label from L-glucose (used as a control for medium carry-over and adsorption) was 16% of that from sucrose. Uptake of label from sucrose did not increase at concentrations above 50 mM, possibly due to a rate-limiting requirement for extracellular hydrolysis. Kinetic analysis revealed both saturable and linear components of uptake for glucose and fructose. The rate of fructose uptake exceeded that of glucose at all concentrations. Fructose uptake at 20 mM was inhibited by NaN 3 , HgCl 2 , dinitrophenol, carbonyl cyanide m-chlorophenylhydrazone, and p-chloromercuribenzenesulfonic acid. Results suggest that sucrose is hydrolyzed prior to uptake, and that fructose is transported preferentially by a carrier sensitive to an external sulfhydryl group inhibitor. Metabolic activity is required for sugar uptake. The specificity of the hexose transporter is currently being investigated

  17. Growth and accumulation of flavan-3-ol in Camellia sinensis through callus culture and suspension culture method

    Directory of Open Access Journals (Sweden)

    Sutini Sutini

    2017-02-01

    Full Text Available This study was aimed to assess flavan-3-ol biomass in C. sinensis through callus cultures and suspension cultures derived from leaf explants. Callus initiation of both cultures were using Murashige and Skoog medium were enriched with plant growth regulators Naphtha-lene Acetic Acid 3.0 mg/L and kinetin 2.0 mg/L. The procedures in this study were: (1 callus initiation by cutting the leaves of C. sinen-sis shoots then planted on Murashige and Skoog medium that were enriched with plant growth regulators, (2 sub callus culture on fresh medium that enriched with the same growth regulators, (3 suspension culture initiation of liquid callus, (4 growth examination of callus and suspension cultures in week 12, (5 examination of qualitative-quantitative content of flavan-3-olin suspension cultures at week 4. The results show that suspension cultures contain biomass flavan-3-ol that increase in the same manner of the increase of callus age and weight

  18. Efficient embryogenic suspension culturing and rapid transformation of a range of elite genotypes of sweet potato (Ipomoea batatas [L.] Lam.).

    Science.gov (United States)

    Yang, Jun; Bi, Hui-Ping; Fan, Wei-Juan; Zhang, Min; Wang, Hong-Xia; Zhang, Peng

    2011-12-01

    Efficient Agrobacterium tumefaciens-mediated transformation was developed using embryogenic suspension cell cultures of elite sweet potato (Ipomoea batatas [L.] Lam.) cultivars, including Ayamurasaki, Sushu2, Sushu9, Sushu11, Wanshu1, Xushu18 and Xushu22. Embryogenic suspension cultures were established in LCP medium using embryogenic calli induced from apical or axillary buds on an induction medium containing 2 mg l(-1) 2,4-D. Suspension cultures were co-cultivated with A. tumefaciens strain LBA4404 harboring the binary plasmid pCAMBIA1301 with the hpt gene as a selectable marker and an intron-interrupted uidA gene as a visible marker. Several key steps of the sweet potato transformation system have been investigated and optimized, including the appropriate antibiotics and their concentrations for suppressing Agrobacterium growth and the optimal doses of hygromycin for transformant selection. A total of 485 putative transgenic plant lines were produced from the transformed calli via somatic embryogenesis and germination to plants under 10 mg l(-1) hygromycin and 200 mg l(-1) cefotaxime. PCR, GUS and Southern blot analyses of the regenerated plants showed that 92.35% of them were transgenic. The number of T-DNA insertions varied from one to three in most transgenic plant lines. Plants showed 100% survival when 308 transgenics were transferred to soil in the greenhouse and then to the field. Most of them were morphologically normal, with the production of storage roots after 3 months of cultivation in the greenhouse or fields. The development of such a robust transformation method suitable to a range of sweet potato genotypes not only provides a routine tool for genetic improvement via transgenesis but also allows us to conduct a functional verification of endogenous genes in sweet potato. Copyright © 2011 Elsevier Ireland Ltd. All rights reserved.

  19. Suspension culture process for H9N2 avian influenza virus (strain Re-2).

    Science.gov (United States)

    Wang, Honglin; Guo, Suying; Li, Zhenguang; Xu, Xiaoqin; Shao, Zexiang; Song, Guicai

    2017-10-01

    H9N2 avian influenza virus has caused huge economic loss for the Chinese poultry industry since it was first identified. Vaccination is frequently used as a control method for the disease. Meanwhile suspension culture has become an important tool for the development of influenza vaccines. To optimize the suspension culture conditions for the avian influenza H9N2 virus (Re-2 strain) in Madin-Darby Canine Kidney (MDCK) cells, we studied the culture conditions for cell growth and proliferation parameters for H9N2 virus replication. MDCK cells were successfully cultured in suspension, from a small scale to industrial levels of production, with passage time and initial cell density being optimized. The influence of pH on the culture process in the reactor has been discussed and the process parameters for industrial production were explored via amplification of the 650L reactor. Subsequently, we cultivated cells at high cell density and harvested high amounts of virus, reaching 10log2 (1:1024). Furthermore an animal experiment was conducted to detect antibody. Compared to the chicken embryo virus vaccine, virus cultured from MDCK suspension cells can produce a higher amount of antibodies. The suspension culture process is simple and cost efficient, thus providing a solid foundation for the realization of large-scale avian influenza vaccine production.

  20. On the assessment of the productivity of suspension cultures of unicellular green algae at defined light conditions

    Energy Technology Data Exchange (ETDEWEB)

    Seiss, U; Borns, E; Boehm, H

    1985-01-01

    A description is given of the possibility of a comparison of the production between different suspension cultures of microalgae at equal and defined light conditions. For this, a variant of the turbidostat technique is used by which with the acid of a phototransistor and the filter combination of red filter/opal glass filter a chlorophyll-equivalent signal is applied for control. The equal light conditions are compared and set by the preparation of the respective absorption profiles. From this one can derive the mean level of irradiation within the suspension cultures and use it as the reference value for the light conditions. By this technique it is possible to set equal light conditions in suspension cultures independent of the given cell sizes, cell shapes and dry matter contents.

  1. Alteration of gene expression during the induction of freezing tolerance in Brassica napus suspension cultures

    International Nuclear Information System (INIS)

    Johnson-Flanagan, A.M.; Singh, J.

    1987-01-01

    Brassica napus suspension-cultured cells can be hardened to a lethal temperature for 50% of the sample of -20 0 C in eight days at room temperature with abscisic acid. During the induction of freezing tolerance, changes were observed in the electrophoretic pattern of [ 35 S]methionine labeled polypeptides. In hardening cells, a 20 kilodalton polypeptide was induced on day 2 and its level increased during hardening. The induction of freezing tolerance with nonmaximal hardening regimens also resulted in increases in the 20 kilodalton polypeptide. The 20 kilodalton polypeptide was associated with a membrane fraction enriched in endoplasmic reticulum and was resolved as a single spot by two-dimensional electrophoresis. In vitro translation of mRNA indicate alteration of gene expression during abscisic acid induction of freezing tolerance. The new mRNA encodes a 20 kilodalton polypeptide associated with increased freezing tolerance induced by either abscisic acid or high sucrose. A 20 kilodalton polypeptide was also translated by mRNA isolated from cold-hardened B. napus plants

  2. Effect of elicitation and feeding on the precursors for the production of taxanes in Taxus baccata L. suspension culture

    Czech Academy of Sciences Publication Activity Database

    Landa, Přemysl; Maršík, Petr; Přibylová, Marie; Vaněk, Tomáš

    2006-01-01

    Roč. 72, č. 11 (2006), s. 1071 ISSN 0032-0943. [Annual Congress on Medicinal Plant Research. 29.08.2006-02.09.2006, Helsinki] R&D Projects: GA MŠk(CZ) 1P04OC926.001 Institutional research plan: CEZ:AV0Z40550506 Keywords : elicitation * suspension culture * taxanes Subject RIV: CE - Biochemistry

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

    Science.gov (United States)

    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. Use of plant cell cultures to study the metabolism of environmental chemicals

    International Nuclear Information System (INIS)

    Sandermann, H. Jr.; Scheel, D.; von der Trenck, T.

    1984-01-01

    The metabolism of the following environmental chemicals has been studied in cell suspension cultures of wheat (Triticum aestivum L.) and soybean (Glycine max L.):2, 4-dichlorophenoxyacetic acid (2,4-D), 2,4,5-trichlorophenoxyacetic acid (2,4,5-T), hexachlorobenzene, pentachlorophenol, diethylhexylphthalate , benzo [alpha] pyrene, and DDT. All chemicals tested, including the persistent ones, were partially metabolized. Polar conjugates predominated in all cases. A covalent incorporation into lignin could be demonstrated for 2,4-D and pentachlorophenol. A specific deposition in the cellular vacuole could be demonstrated for the beta-D-glucopyranoside conjugates derived from 2,4-D. A rapid assay procedure to evaluate the metabolism of a given 14 C-labeled chemical in plant cell suspension cultures is described. This procedure requires about 1 week, and the reproducibility of the results obtained has been assessed

  5. Pretreatment of Parsley (Petroselinum crispum L.) Suspension Cultures with Methyl Jasmonate Enhances Elicitation of Activated Oxygen Species.

    Science.gov (United States)

    Kauss, H.; Jeblick, W.; Ziegler, J.; Krabler, W.

    1994-01-01

    Suspension-cultured cells of parsley (Petroselinum crispum L.) were used to demonstrate an influence of jasmonic acid methyl ester (JAME) on the elicitation of activated oxygen species. Preincubation of the cell cultures for 1 d with JAME greatly enhanced the subsequent induction by an elicitor preparation from cell walls of Phytophtora megasperma f. sp. glycinea (Pmg elicitor) and by the polycation chitosan. Shorter preincubation times with JAME were less efficient, and the effect was saturated at about 5 [mu]M JAME. Treatment of the crude Pmg elicitor with trypsin abolished induction of activated oxygen species, an effect similar to that seen with elicitation of coumarin secretion. These results suggest that JAME conditioned the parsley suspension cells in a time-dependent manner to become more responsive to elicitation, reminiscent of developmental effects caused by JAME in whole plants. It is interesting that pretreatment of the parsley cultures with 2,6-dichloroisonicotinic and 5-chlorosalicylic acid only slightly enhanced the elicitation of activated oxygen species, whereas these substances greatly enhanced the elicitation of coumarin secretion. Therefore, these presumed inducers of systemic acquired resistance exhibit a specificity different from JAME. PMID:12232189

  6. Cloning higher plants from aseptically cultured tissues and cells

    Science.gov (United States)

    Krikorian, A. D.

    1982-01-01

    A review of aseptic culture methods for higher plants is presented, which focuses on the existing problems that limit or prevent the full realization of cloning plants from free cells. It is shown that substantial progress in clonal multiplication has been made with explanted stem tips or lateral buds which can be stimulated to produce numerous precocious axillary branches. These branches can then be separated or subdivided and induced to root in order to yield populations of genetically and phenotypically uniorm plantlets. Similarly, undifferentiated calluses can sometimes be induced to form shoots and/or roots adventitiously. Although the cell culture techniques required to produce somatic embryos are presently rudimentary, steady advances are being made in learning how to stimulate formation of somatic or adventive embryos from totipotent cells grown in suspension cultures. It is concluded that many problems exist in the producing and growing of totipotent or morphogenetically competent cell suspensions, but the potential benefits are great.

  7. A transgenic plant cell-suspension system for expression of epitopes on chimeric Bamboo mosaic virus particles.

    Science.gov (United States)

    Muthamilselvan, Thangarasu; Lee, Chin-Wei; Cho, Yu-Hsin; Wu, Feng-Chao; Hu, Chung-Chi; Liang, Yu-Chuan; Lin, Na-Sheng; Hsu, Yau-Heiu

    2016-01-01

    We describe a novel strategy to produce vaccine antigens using a plant cell-suspension culture system in lieu of the conventional bacterial or animal cell-culture systems. We generated transgenic cell-suspension cultures from Nicotiana benthamiana leaves carrying wild-type or chimeric Bamboo mosaic virus (BaMV) expression constructs encoding the viral protein 1 (VP1) epitope of foot-and-mouth disease virus (FMDV). Antigens accumulated to high levels in BdT38 and BdT19 transgenic cell lines co-expressing silencing suppressor protein P38 or P19. BaMV chimeric virus particles (CVPs) were subsequently purified from the respective cell lines (1.5 and 2.1 mg CVPs/20 g fresh weight of suspended biomass, respectively), and the resulting CVPs displayed VP1 epitope on the surfaces. Guinea pigs vaccinated with purified CVPs produced humoral antibodies. This study represents an important advance in the large-scale production of immunopeptide vaccines in a cost-effective manner using a plant cell-suspension culture system. © 2015 Society for Experimental Biology, Association of Applied Biologists and John Wiley & Sons Ltd.

  8. Saccharomyces cerevisiae gene expression changes during rotating wall vessel suspension culture

    Science.gov (United States)

    Johanson, Kelly; Allen, Patricia L.; Lewis, Fawn; Cubano, Luis A.; Hyman, Linda E.; Hammond, Timothy G.

    2002-01-01

    This study utilizes Saccharomyces cerevisiae to study genetic responses to suspension culture. The suspension culture system used in this study is the high-aspect-ratio vessel, one type of the rotating wall vessel, that provides a high rate of gas exchange necessary for rapidly dividing cells. Cells were grown in the high-aspect-ratio vessel, and DNA microarray and metabolic analyses were used to determine the resulting changes in yeast gene expression. A significant number of genes were found to be up- or downregulated by at least twofold as a result of rotational growth. By using Gibbs promoter alignment, clusters of genes were examined for promoter elements mediating these genetic changes. Candidate binding motifs similar to the Rap1p binding site and the stress-responsive element were identified in the promoter regions of differentially regulated genes. This study shows that, as in higher order organisms, S. cerevisiae changes gene expression in response to rotational culture and also provides clues for investigations into the signaling pathways involved in gravitational response.

  9. Preparation of labelled lipids by the use of plant cell cultures

    International Nuclear Information System (INIS)

    Mangold, H.K.

    1978-01-01

    The preparation of some radioacitvely labelled lipids by the use of plant cell cultures is discussed and further applications of the new method are suggested. Cell suspension cultures of rape (Brassica napus) and soya (Glycine max) have been used for the preparation of lipids labelled with radioisotopes. Radioactive acetic acid as well as various long-chain fatty acids are readily incorporated into the neutral and ionic lipids of plant cell cultures. In addition, 14 C-labelled glycerol, ethanolamine and choline are well utilized by the cells. Randomly labelled lipids have been obtained by incubating cell suspension cultures of rape and soya with [1- 14 C] acetic acid, and uniformly labelled lipids have been isolated from cultures that had been incubated with a mixture of [1- 14 C] acetic acid plus [2- 14 C] acetic acid. The use of techniques of plant cell cultures for the preparation of lipds labelled with stable or radioactive isotopesappears particularly rewarding because the uptake of precursors by the cells and their incorporation into various lipid compounds proceeds rapidly and often quanitatively.This new approach should be useful also for the biosynthesis of lipids whose acyl moieties contain a spn radical, a fluorescent group, or a light-sensitive label. Thus, plant cell cultures constitute valuable new tools for the biosynthetic preparation of a great variety of labelled lipids. (A.G.)

  10. Embryogenic callus formation, growth and regeneration in callus and suspension cultures of Miscanthus x ogiformis Honda 'Giganteus' as affected by proline

    DEFF Research Database (Denmark)

    Holme, Inger Bæksted; Krogstrup, Peter; Hansen, Jürgen

    1997-01-01

    .6 M 2,4-dichlorophenoxyacetic acid. Shoot apices and leaves from in vitro-propagated shoots, and immature inflorescences from greenhouse-grown plants were used as explants for callus induction and formation. Suspension cultures initiated from embryogenic callus of immature inflorescences were used...

  11. Optimization of callus and cell suspension cultures of Barringtonia racemosa (Lecythidaceae family for lycopene production Otimização de culturas de suspensões de calos e células de Barringtonia racemosa (família Lecythidaceae para produção de licopeno

    Directory of Open Access Journals (Sweden)

    Mandana Behbahani

    2011-02-01

    Full Text Available Lycopene is present in a range of fresh fruits and vegetables, especially in the leaves of Barringtonia racemosa. The traditional lycopene extraction from the plant is being employed instead of an easy propagation technique like cell culture process from the leaf explants. We intend to assess how lycopene could be extracted via tissue culture under light (illuminance: 8,200 lux under white fluorescent lamps, photoperiod 16 h per day at 25ºC and dark. Leaf explants of Barringtonia racemosa were cultured on modified Murashige and Skoog (MS, Woody Plant Medium (WPM and B5 media, supplemented with different concentrations of 2,4-Dichlorophenoxyacetic acid (2,4-D. Optimal conditions for callus induction and maintenance under both dark and light were investigated, and growth and lycopene accumulation were evaluated. Among media with different concentrations of 2,4-D, fast growing, friable callus initiated within three weeks after culturing on WPM basal medium supplemented with 2.0 mg L-1 (weight per volume of 2,4-D, whereas callus induction in explants cultured on all other media started only after five weeks. Calli were subcultured once every fortnight. Pale yellow and green calli developed under conditions of dark and light respectively were then selected for evaluation of their lycopene contents. An improved reversed phase of high performance liquid chromatography (HPLC method was used for a selective chemical determination of the lycopene content. Light induced lycopene production; and likewise maximum lycopene level incubated in light was higher than those incubated in darkness. The best growth rates of callus and cell suspension were achieved in WPM and B5 media respectively. The production of lycopene was growth-dependent through analysis of growth and lycopene content of both callus and cell suspension cultures.O licopeno está presente numa série de frutas frescas e hortaliças principalmente na folhas de Barringtonia racemosa. A extra

  12. Effects of aluminum on organic acid metabolism and secretion by red spruce cell suspension cultures and the reversal of Al effects on growth and polyamine metabolism by exogenous organic acids

    Science.gov (United States)

    Rakesh Minocha; Stephanie Long

    2004-01-01

    In the absence of added Al, the concentration of succinate in cultured red spruce (Picea rubens Sarg.) cells was 15-20 times higher (> 600 nmol g-1FW) than that of citrate or oxalate and 4-6 times higher than that of malate. Addition of AICIJ (effective monomeric Al concentrations of 0.23 and 0.48...

  13. Plant Cell Cultures as Source of Cosmetic Active Ingredients

    Directory of Open Access Journals (Sweden)

    Ani Barbulova

    2014-04-01

    Full Text Available The last decades witnessed a great demand of natural remedies. As a result, medicinal plants have been increasingly cultivated on a commercial scale, but the yield, the productive quality and the safety have not always been satisfactory. Plant cell cultures provide useful alternatives for the production of active ingredients for biomedical and cosmetic uses, since they represent standardized, contaminant-free and biosustainable systems, which allow the production of desired compounds on an industrial scale. Moreover, thanks to their totipotency, plant cells grown as liquid suspension cultures can be used as “biofactories” for the production of commercially interesting secondary metabolites, which are in many cases synthesized in low amounts in plant tissues and differentially distributed in the plant organs, such as roots, leaves, flowers or fruits. Although it is very widespread in the pharmaceutical industry, plant cell culture technology is not yet very common in the cosmetic field. The aim of the present review is to focus on the successful research accomplishments in the development of plant cell cultures for the production of active ingredients for cosmetic applications.

  14. Antioxidant isoenzyme responses to nickel-induced stress in tobacco cell suspension culture Resposta de isoenzimas antioxidantes ao estresse induzido por níquel em cultura de células em suspensão de fumo

    Directory of Open Access Journals (Sweden)

    Georgia Bertoni Pompeu

    2008-01-01

    Full Text Available Exposure to nickel (Ni at high concentrations can lead to production of reactive oxygen species (ROS resulting in oxidative damage at the cellular level. We investigated the antioxidative responses of Nicotiana tabacum cv BY-2 cell suspension to Ni stress (0.075 and 0.75 mM NiCl2 over a 72 h period with special attention to potential alterations in isoenzymes of superoxide dismutase (SOD, catalase (CAT and glutathione reductase (GR. Two main SOD isoenzymes were observed, a Mn-SOD (band I and a Fe-SOD (band II, as well as one CAT isoenzyme and four GR isoenzymes. Activity staining analysis revealed that CAT activity plays a major role in the early response to Ni-induced oxidative stress, particularly when the Ni concentration used was low, whilst a specific GR isoenzyme appears to respond to the Ni-induced oxidative stress when a much higher Ni concentration was used to induce the stress for the same period of treatment. These results illustrate the importance and advantages of determining individual isoenzyme activities.A exposição ao níquel (Ni, em altas concentrações, pode levar à produção de espécies reativas de oxigênio (EAOs, resultando em danos oxidativos em nível celular. Foram investigadas as respostas antioxidativas de células em suspensão do cultivar BY-2 de Nicotiana tabacum submetidas ao estresse por Ni (0.075 e 0.75 mM de NiCl2 por 72 h, com atenção especial às alterações potencias em isoenzimas de superóxido dismutase (SOD, catalase (CAT e glutatione redutase (GR. Duas principais isoenzimas de SOD foram observadas, uma Mn-SOD (banda I e outra Fe-SOD (banda II, bem como uma isoenzima CAT e quatro isoenzimas de GR. As análises revelaram que a atividade de CAT tem papel principal no momento inicial de resposta ao estresse oxidativo induzido por Ni, particularmente, quando sua concentração foi mais baixa, enquanto uma isoenzima específica de GR parece responder a este estresse na concentração mais alta de Ni

  15. The Specific Nature of Plant Cell Wall Polysaccharides 1

    Science.gov (United States)

    Nevins, Donald J.; English, Patricia D.; Albersheim, Peter

    1967-01-01

    Polysaccharide compositions of cell walls were assessed by quantitative analyses of the component sugars. Cell walls were hydrolyzed in 2 n trifluoroacetic acid and the liberated sugars reduced to their respective alditols. The alditols were acetylated and the resulting alditol acetates separated by gas chromatography. Quantitative assay of the alditol acetates was accomplished by electronically integrating the detector output of the gas chromatograph. Myo-inositol, introduced into the sample prior to hydrolysis, served as an internal standard. The cell wall polysaccharide compositions of plant varieties within a given species are essentially identical. However, differences in the sugar composition were observed in cell walls prepared from different species of the same as well as of different genera. The fact that the wall compositions of different varieties of the same species are the same indicates that the biosynthesis of cell wall polysaccharides is genetically regulated. The cell walls of various morphological parts (roots, hypocotyls, first internodes and primary leaves) of bean plants were each found to have a characteristic sugar composition. It was found that the cell wall sugar composition of suspension-cultured sycamore cells could be altered by growing the cells on different carbon sources. This demonstrates that the biosynthesis of cell wall polysaccharides can be manipulated without fatal consequences. PMID:16656594

  16. EVALUATING THE ACCUMULATION TREND OF L-DOPA IN DARK-GERMINATED SEEDS AND SUSPENSION CULTURES OF Phaseolus vulgaris L. BY AN EFFICIENT UV-SPECTROPHOTOMETRIC METHOD

    Directory of Open Access Journals (Sweden)

    Samira Rahmani-Nezhad

    Full Text Available Seed germination and plant cell cultures provide an alternative mean for producing secondary metabolites. The present study is an attempt to evaluate the effect of seed dark germination and some elicitors and precursors on the production of L-DOPA in Phaseolus vulgaris L. Callus cultured on Murashige and Skoog medium supplemented with various concentrations of different plant growth regulators. L-DOPA produced was quantified by UV-spectrophotometric method. In this study, a user-friendly, quick, and economical UV-spectrophotometric method was described to determine L-DOPA content in extracts from 33 biotypes of Phaseolus vulgaris L. The method is based on the nitrosation of L-DOPA to form a yellow solution and then formation of a red solution by adding base which is measurable at 470 nm. According to our statistical studies, this method showed high efficiency and selectivity for quantitative determination of L-DOPA in herbal extracts from dried plant seeds, dark-germinated seeds and callus cultures. L-DOPA content in dark-germinated seeds and suspension cultures increased significantly to approximately several-fold compared to the control. The implication from this study is that elicitor treatment and precursor feeding of Phaseolus vulgaris L. can significantly improve the parkinson’s relevant L-DOPA content.

  17. Anaerobic bacteria grow within Candida albicans biofilms and induce biofilm formation in suspension cultures.

    Science.gov (United States)

    Fox, Emily P; Cowley, Elise S; Nobile, Clarissa J; Hartooni, Nairi; Newman, Dianne K; Johnson, Alexander D

    2014-10-20

    The human microbiome contains diverse microorganisms, which share and compete for the same environmental niches. A major microbial growth form in the human body is the biofilm state, where tightly packed bacterial, archaeal, and fungal cells must cooperate and/or compete for resources in order to survive. We examined mixed biofilms composed of the major fungal species of the gut microbiome, Candida albicans, and each of five prevalent bacterial gastrointestinal inhabitants: Bacteroides fragilis, Clostridium perfringens, Escherichia coli, Klebsiella pneumoniae, and Enterococcus faecalis. We observed that biofilms formed by C. albicans provide a hypoxic microenvironment that supports the growth of two anaerobic bacteria, even when cultured in ambient oxic conditions that are normally toxic to the bacteria. We also found that coculture with bacteria in biofilms induces massive gene expression changes in C. albicans, including upregulation of WOR1, which encodes a transcription regulator that controls a phenotypic switch in C. albicans, from the "white" cell type to the "opaque" cell type. Finally, we observed that in suspension cultures, C. perfringens induces aggregation of C. albicans into "mini-biofilms," which allow C. perfringens cells to survive in a normally toxic environment. This work indicates that bacteria and C. albicans interactions modulate the local chemistry of their environment in multiple ways to create niches favorable to their growth and survival. Copyright © 2014 Elsevier Ltd. All rights reserved.

  18. Effects of several physiochemical factors on cell growth and gallic ...

    African Journals Online (AJOL)

    The production of gallic acid in cell suspension culture of Acer ginnala Maxim was studied. Some physiochemical factors and chemical substances effect on the cell growth and the production of gallic acid were investigated. Cells harvested from plant tissue culture were extracted and applied to high performance liquid ...

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

    Science.gov (United States)

    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. Induced accumulation of 20-hydroxyecdysone in cell suspension ...

    African Journals Online (AJOL)

    Administrator

    2011-09-12

    Sep 12, 2011 ... This study describes the effects of culture medium, culture temperature, sucrose concentration and cholesterol feeding on cell growth and 20-hydroxyecdysone production in suspension cultures of Vitex glabrata, an important medicinal plant in Thailand. Cell growth and 20-hydroxyecdysone production.

  1. Induced accumulation of 20-hydroxyecdysone in cell suspension ...

    African Journals Online (AJOL)

    This study describes the effects of culture medium, culture temperature, sucrose concentration and cholesterol feeding on cell growth and 20-hydroxyecdysone production in suspension cultures of Vitex glabrata, an important medicinal plant in Thailand. Cell growth and 20-hydroxyecdysone production were not significantly ...

  2. Growth characteristics and nutrient depletion of Miscanthus x ogiformis Honda 'Giganteus' suspension cultures

    DEFF Research Database (Denmark)

    Holme, Inger Bæksted

    1998-01-01

    The growth characteristics and nutrient depletion in suspension cultures of Miscanthus ogiformis Honda ‘Giganteus' grown in media containing either Murashige and Skoog or N6 basal nutrient salts were studied during a culture period of 15 days. Proline was added to both media in concentrations from...... to the MS suspension cultures. Sucrose was hydrolysed into its monosaccharide components in the culture medium. Glucose was depleted faster than fructose indicating a preference for glucose as a carbohydrate source of the M. ogiformis cultures. The high water uptake by the suspension aggregates 12 to 15...

  3. Plant stem cell niches.

    Science.gov (United States)

    Aichinger, Ernst; Kornet, Noortje; Friedrich, Thomas; Laux, Thomas

    2012-01-01

    Multicellular organisms possess pluripotent stem cells to form new organs, replenish the daily loss of cells, or regenerate organs after injury. Stem cells are maintained in specific environments, the stem cell niches, that provide signals to block differentiation. In plants, stem cell niches are situated in the shoot, root, and vascular meristems-self-perpetuating units of organ formation. Plants' lifelong activity-which, as in the case of trees, can extend over more than a thousand years-requires that a robust regulatory network keep the balance between pluripotent stem cells and differentiating descendants. In this review, we focus on current models in plant stem cell research elaborated during the past two decades, mainly in the model plant Arabidopsis thaliana. We address the roles of mobile signals on transcriptional modules involved in balancing cell fates. In addition, we discuss shared features of and differences between the distinct stem cell niches of Arabidopsis.

  4. Evaluation of Antioxidant and Antibacterial Potentials of Nigella sativa L. Suspension Cultures under Elicitation

    Directory of Open Access Journals (Sweden)

    Hera Chaudhry

    2015-01-01

    Full Text Available Nigella sativa L. (family Ranunculaceae is an annual herb of immense medicinal properties because of its major active components (i.e., thymoquinone (TQ, thymohydroquinone (THQ, and thymol (THY. Plant tissue culture techniques like elicitation, Agrobacterium mediated transformation, hairy root culture, and so on, are applied for substantial metabolite production. This study enumerates the antibacterial and antioxidant potentials of N. sativa epicotyl suspension cultures under biotic and abiotic elicitation along with concentration optimization of the elicitors for enhanced TQ and THY production. Cultures under different concentrations of pectin and manganese chloride (MnCl2 elicitation (i.e., 5 mg/L, 10 mg/L, and 15 mg/L showed that the control, MnCl2 10 mg/L, and pectin 15 mg/L suspension extracts greatly inhibited the growth of E. coli, S. typhimurium, and S. aureus (MIC against E. coli, i.e., 2.35±0.8, 2.4±0.2, and 2.46±0.5, resp.. Elicitation decreased SOD enzyme activity whereas CAT enzyme activity increased remarkably under MnCl2 elicitation. MnCl2 10 mg/L and pectin 15 mg/L elicitation enhanced the DPPH radical inhibition ability, but ferric scavenging activity was comparable to the control. TQ and THY were quantified by LC-MS/MS in the cultures with high bioactive properties revealing maximum content under MnCl2 10 mg/L elicitation. Therefore, MnCl2 elicitation can be undertaken on large scale for sustainable metabolite production.

  5. Evaluation of Antioxidant and Antibacterial Potentials of Nigella sativa L. Suspension Cultures under Elicitation.

    Science.gov (United States)

    Chaudhry, Hera; Fatima, Nida; Ahmad, Iffat Zareen

    2015-01-01

    Nigella sativa L. (family Ranunculaceae) is an annual herb of immense medicinal properties because of its major active components (i.e., thymoquinone (TQ), thymohydroquinone (THQ), and thymol (THY)). Plant tissue culture techniques like elicitation, Agrobacterium mediated transformation, hairy root culture, and so on, are applied for substantial metabolite production. This study enumerates the antibacterial and antioxidant potentials of N. sativa epicotyl suspension cultures under biotic and abiotic elicitation along with concentration optimization of the elicitors for enhanced TQ and THY production. Cultures under different concentrations of pectin and manganese chloride (MnCl2) elicitation (i.e., 5 mg/L, 10 mg/L, and 15 mg/L) showed that the control, MnCl2 10 mg/L, and pectin 15 mg/L suspension extracts greatly inhibited the growth of E. coli, S. typhimurium, and S. aureus (MIC against E. coli, i.e., 2.35 ± 0.8, 2.4 ± 0.2, and 2.46 ± 0.5, resp.). Elicitation decreased SOD enzyme activity whereas CAT enzyme activity increased remarkably under MnCl2 elicitation. MnCl2 10 mg/L and pectin 15 mg/L elicitation enhanced the DPPH radical inhibition ability, but ferric scavenging activity was comparable to the control. TQ and THY were quantified by LC-MS/MS in the cultures with high bioactive properties revealing maximum content under MnCl2 10 mg/L elicitation. Therefore, MnCl2 elicitation can be undertaken on large scale for sustainable metabolite production.

  6. Regeneration from embryogenic callus and suspension cultures of ...

    African Journals Online (AJOL)

    ehab

    2012-04-25

    Apr 25, 2012 ... cultures of the wild medicinal plant Cymbopogon schoenanthus ... nardus, C. martini, C. citratus and C. flexuosus are the source of palmerosa, citronella, lemon-grass and oil of. Malabar ...... marketing of essential oils. J. Med.

  7. Plant stem cell niches.

    Science.gov (United States)

    Stahl, Yvonne; Simon, Rüdiger

    2005-01-01

    Stem cells are required to support the indeterminate growth style of plants. Meristems are a plants stem cell niches that foster stem cell survival and the production of descendants destined for differentiation. In shoot meristems, stem cell fate is decided at the populational level. The size of the stem cell domain at the meristem tip depends on signals that are exchanged with cells of the organizing centre underneath. In root meristems, individual stem cells are controlled by direct interaction with cells of the quiescent centre that lie in the immediate neighbourhood. Analysis of the interactions and signaling processes in the stem cell niches has delivered some insights into the molecules that are involved and revealed that the two major niches for plant stem cells are more similar than anticipated.

  8. Induction and Analysis of the Alkaloid Mitragynine Content of a Mitragyna speciosa Suspension Culture System upon Elicitation and Precursor Feeding

    Directory of Open Access Journals (Sweden)

    Nor Nahazima Mohamad Zuldin

    2013-01-01

    Full Text Available This study aimed to determine the effects of different concentrations and combinations of the phytohormones 2,4-dichlorophenoxy acetic acid (2,4-D, kinetin, 6-benzylaminopurine (BAP, and 1-naphthaleneacetic acid (NAA on callus induction and to demonstrate the role of elicitors and exogenous precursors on the production of mitragynine in a Mitragyna speciosa suspension culture. The best callus induction was achieved from petiole explants cultured on WPM that was supplemented with 4 mg L−1 2, 4-D (70.83%. Calli were transferred to liquid media and agitated on rotary shakers to establish Mitragyna speciosa cell suspension cultures. The optimum settled cell volume was achieved in the presence of WPM that contained 3 mg L−1 2,4-D and 3% sucrose (9.47±0.4667 mL. The treatment of cultures with different concentrations of yeast extract and salicylic acid for different inoculation periods revealed that the highest mitragynine content as determined by HPLC was achieved from the culture treated with 250 mg L−1 yeast extract (9.275±0.082 mg L−1 that was harvested on day 6 of culturing; salicylic acid showed low mitragynine content in all concentrations used. Tryptophan and loganin were used as exogenous precursors; the highest level of mitragynine production was achieved in cultures treated with 3 μM tryptophan and harvested at 6 days (13.226±1.98 mg L−1.

  9. Regeneration from embryogenic callus and suspension cultures of ...

    African Journals Online (AJOL)

    ehab

    2012-04-25

    Apr 25, 2012 ... Micropropagation, through seed culture has been studied in C. martinii ... Effect of 2,4-D on total and embryogenic callus production ... ethanol for 1 min, followed by immersion in 20% Clorox (NaOCl ... Three flasks from each treatment were cultured. ... shaker at 110 rpm. ...... Plants cultivated in bioreactor of.

  10. Visual selection and maintenance of the cell lines with high plant regeneration ability and low ploidy level in Dianthus acicularis by monitoring with flow cytometry analysis.

    Science.gov (United States)

    Shiba, Tomonori; Mii, Masahiro

    2005-12-01

    Efficient plant regeneration system from cell suspension cultures was established in D. acicularis (2n=90) by monitoring ploidy level and visual selection of the cultures. The ploidy level of the cell cultures closely related to the shoot regeneration ability. The cell lines comprising original ploidy levels (2C+4C cells corresponding to DNA contents of G1 and G2 cells of diploid plant, respectively) showed high regeneration ability, whereas those containing the cells with 8C or higher DNA C-values showed low or no regeneration ability. The highly regenerable cell lines thus selected consisted of compact cell clumps with yellowish color and relatively moderate growth, suggesting that it is possible to select visually the highly regenerable cell lines with the original ploidy level. All the regenerated plantlets from the highly regenerable cell cultures exhibited normal phenotypes and no variations in ploidy level were observed by flow cytometry (FCM) analysis.

  11. Effect of salts (NaCl and Na2CO3) on callus and suspension culture of Stevia rebaudiana for Steviol glycoside production.

    Science.gov (United States)

    Gupta, Pratibha; Sharma, Satyawati; Saxena, Sanjay

    2014-03-01

    Steviol glycosides are natural non-caloric sweeteners which are extracted from the leaves of Stevia rebaudiana plant. Present study deals the effect of salts (NaCl and Na2CO3) on callus and suspension culture of Stevia plant for steviol glycoside (SGs) production. Yellow-green and compact calli obtained from in vitro raised Stevia leaves sub-cultured on MS medium supplemented with 2.0 mg l(-1) NAA and different concentrations of NaCl (0.05-0.20%) and Na2CO3 (0.0125-0.10%) for 2 weeks, and incubated at 24 ± 1 °C and 22.4 μmol m(-2) s(-1) light intensity provided by white fluorescent tubes for 16 h. Callus and suspension biomass cultured on salts showed less growth as well as browning of medium when compared with control. Quantification of SGs content in callus culture (collected on 15th day) and suspension cultures (collected at 10th and 15th days) treated with and without salts were analyzed by HPLC. It was found that abiotic stress induced by the salts increased the concentration of SGs significantly. In callus, the quantity of SGs got increased from 0.27 (control) to 1.43 and 1.57% with 0.10% NaCl, and 0.025% Na2CO3, respectively. However, in case of suspension culture, the same concentrations of NaCl and Na2CO3 enhanced the SGs content from 1.36 (control) to 2.61 and 5.14%, respectively, on the 10th day.

  12. Growing Arabidopsis in vitro: cell suspensions, in vitro culture, and regeneration.

    Science.gov (United States)

    Barkla, Bronwyn J; Vera-Estrella, Rosario; Pantoja, Omar

    2014-01-01

    An understanding of basic methods in Arabidopsis tissue culture is beneficial for any laboratory working on this model plant. Tissue culture refers to the aseptic growth of cells, organs, or plants in a controlled environment, in which physical, nutrient, and hormonal conditions can all be easily manipulated and monitored. The methodology facilitates the production of a large number of plants that are genetically identical over a relatively short growth period. Techniques, including callus production, cell suspension cultures, and plant regeneration, are all indispensable tools for the study of cellular biochemical and molecular processes. Plant regeneration is a key technology for successful stable plant transformation, while cell suspension cultures can be exploited for metabolite profiling and mining. In this chapter we report methods for the successful and highly efficient in vitro regeneration of plants and production of stable cell suspension lines from leaf explants of both Arabidopsis thaliana and Arabidopsis halleri.

  13. Changes in auxin level in the course of growth of a sunflower crown-gall suspension culture

    Directory of Open Access Journals (Sweden)

    Zofia Chirek

    2014-01-01

    Full Text Available The auxin level in the cell mass and culture medium was determined by means of the Avena straight caleoptile test in various periods of the suspension culture cycle of the sunflower crown-gall tumour. The investigations were performed in the course of the zero passage (PO and first one (Pl, differing in their time of duration of maximum growth and its intensity. In both passages the intra- and extra-cellular auxin levels reach values of the same order. At the beginning of the maximal growth phase the activity corresponding to IAA in the cells prevails over that of the other auxin-like compounds. This disproportion diminishes with further development of the culture, and with the beginning of the stationary phase the cellular IAA level is lower than that of the remaining auxin-like compounds. The short phase of maximal growth (PO occurs with an auxin level decreasing in the cell mass and increasing in the medium, and towards the end of the cycle these levels become equal. During the long phase of maximal growth (Pl the total amount of auxins in the cells increases and is 2-3 times higher than in the medium, whereas IAA in the cells remains at a constant level. These results suggest that the participation of IAA in the intracellular pool of auxin-like substances is decisive for the mitotic activity of the cells and maintenance of growth in the culture.

  14. Colour bio-factories: Towards scale-up production of anthocyanins in plant cell cultures.

    Science.gov (United States)

    Appelhagen, Ingo; Wulff-Vester, Anders Keim; Wendell, Micael; Hvoslef-Eide, Anne-Kathrine; Russell, Julia; Oertel, Anne; Martens, Stefan; Mock, Hans-Peter; Martin, Cathie; Matros, Andrea

    2018-06-08

    Anthocyanins are widely distributed, glycosylated, water-soluble plant pigments, which give many fruits and flowers their red, purple or blue colouration. Their beneficial effects in a dietary context have encouraged increasing use of anthocyanins as natural colourants in the food and cosmetic industries. However, the limited availability and diversity of anthocyanins commercially have initiated searches for alternative sources of these natural colourants. In plants, high-level production of secondary metabolites, such as anthocyanins, can be achieved by engineering of regulatory genes as well as genes encoding biosynthetic enzymes. We have used tobacco lines which constitutively produce high levels of cyanidin 3-O-rutinoside, delphinidin 3-O-rutinoside or a novel anthocyanin, acylated cyanidin 3-O-(coumaroyl) rutinoside to generate cell suspension cultures. The cell lines are stable in their production rates and superior to conventional plant cell cultures. Scale-up of anthocyanin production in small scale fermenters has been demonstrated. The cell cultures have also proven to be a suitable system for production of 13 C-labelled anthocyanins. Our method for anthocyanin production is transferable to other plant species, such as Arabidopsis thaliana, demonstrating the potential of this approach for making a wide range of highly-decorated anthocyanins. The tobacco cell cultures represent a customisable and sustainable alternative to conventional anthocyanin production platforms and have considerable potential for use in industrial and medical applications of anthocyanins. Copyright © 2018 The Authors. Published by Elsevier Inc. All rights reserved.

  15. Plant cell culture initiation

    NARCIS (Netherlands)

    Hall, R.D.

    2000-01-01

    The use of cultured plant cells in either organized or unorganized form has increased vey considerably in the last 10-15 yr. Many new technologies have been developed and applications in both fundamental and applied research have led to the development of some powerful tools for improving our

  16. Loss of the ability to generate large burst-forming unit-like megakaryocytic colonies from thawed cord blood in semisolid cultures after short term suspension culture.

    Science.gov (United States)

    Eskola, M; Bäckman, S; Möttönen, S; Kekomäki, R

    2015-04-01

    Total colony-forming cells from thawed cord blood units (CBUs) include megakaryocytic colony-forming units (CFU-Mks), which survive the freezing process. The aim of this study was to evaluate whether different megakaryocytic progenitors from unseparated CBUs survive the freezing process and a short-term liquid culture. Thawed samples of CBUs were cultured in liquid medium. During the cultures, serial samples were drawn to assess the growth of different megakaryocytic progenitors in a semisolid collagen medium with identical cytokines as in the liquid medium. Megakaryocytic cells were detected using immunohistochemistry and flow cytometry. In suspension culture, the megakaryocytic progenitors almost completely lost the ability to generate large (burst-forming unit-like, BFU-like) megakaryocytic colonies in semisolid cultures (large colonies, median count per chamber d0: 7.25 vs. d7: 1.5; P culture in suspension resulted in the decline of small colonies as well (d7: 16.0 vs. d14: 5.75; P = 0.0088). Total CFU-Mk count declined from 23.3 (range 12.5-34.0) at d0 to 7.25 (range 1.0-13.5) at d14 (P culture after a short suspension culture. Small CFU-Mks were observed throughout the cultures. It may be that the BFU-Mk colonies matured and acquired CFU-Mk behaviour. © 2014 International Society of Blood Transfusion.

  17. Hybrid proline-rich proteins: novel players in plant cell elongation?

    Science.gov (United States)

    Dvořáková, Lenka; Srba, Miroslav; Opatrny, Zdenek; Fischer, Lukas

    2012-01-01

    Background and Aims Hybrid proline-rich proteins (HyPRPs) represent a large family of putative cell-wall proteins characterized by the presence of a variable N-terminal domain and a conserved C-terminal domain that is related to non-specific lipid transfer proteins. The function of HyPRPs remains unclear, but their widespread occurrence and abundant expression patterns indicate that they may be involved in a basic cellular process. Methods To elucidate the cellular function of HyPRPs, we modulated the expression of three HyPRP genes in tobacco (Nicotiana tabacum) BY-2 cell lines and in potato (Solanum tuberosum) plants. Key Results In BY-2 lines, over-expression of the three HyPRP genes with different types of N-terminal domains resulted in similar phenotypic changes, namely increased cell elongation, both in suspension culture and on solid media where the over-expression resulted in enhanced calli size. The over-expressing cells showed increased plasmolysis in a hypertonic mannitol solution and accelerated rate of protoplast release, suggesting loosening of the cell walls. In contrast to BY-2 lines, no phenotypic changes were observed in potato plants over-expressing the same or analogous HyPRP genes, presumably due to more complex compensatory mechanisms in planta. Conclusions Based on the results from BY-2 lines, we propose that HyPRPs, more specifically their C-terminal domains, represent a novel group of proteins involved in cell expansion. PMID:22028464

  18. Calcium in plant cells

    Directory of Open Access Journals (Sweden)

    V. V. Schwartau

    2014-04-01

    Full Text Available The paper gives the review on the role of calcium in many physiological processes of plant organisms, including growth and development, protection from pathogenic influences, response to changing environmental factors, and many other aspects of plant physiology. Initial intake of calcium ions is carried out by Ca2+-channels of plasma membrane and they are further transported by the xylem owing to auxins’ attractive ability. The level of intake and selectivity of calcium transport to ove-ground parts of the plant is controlled by a symplast. Ca2+enters to the cytoplasm of endoderm cells through calcium channels on the cortical side of Kaspary bands, and is redistributed inside the stele by the symplast, with the use of Ca2+-АТPases and Ca2+/Н+-antiports. Owing to regulated expression and activity of these calcium transporters, calclum can be selectively delivered to the xylem. Important role in supporting calcium homeostasis is given to the vacuole which is the largest depo of calcium. Regulated quantity of calcium movement through the tonoplast is provided by a number of potential-, ligand-gated active transporters and channels, like Ca2+-ATPase and Ca2+/H+ exchanger. They are actively involved in the inactivation of the calcium signal by pumping Ca2+ to the depo of cells. Calcium ATPases are high affinity pumps that efficiently transfer calcium ions against the concentration gradient in their presence in the solution in nanomolar concentrations. Calcium exchangers are low affinity, high capacity Ca2+ transporters that are effectively transporting calcium after raising its concentration in the cell cytosol through the use of protons gradients. Maintaining constant concentration and participation in the response to stimuli of different types also involves EPR, plastids, mitochondria, and cell wall. Calcium binding proteins contain several conserved sequences that provide sensitivity to changes in the concentration of Ca2+ and when you

  19. Hydrolytic enzymes in the central vacuole of plant cells.

    Science.gov (United States)

    Boller, T; Kende, H

    1979-06-01

    The hydrolase content of vacuoles isolated from protoplasts of suspension-cultured tobacco cells, of tulip petals, and of pineapple leaves, and the sedimentation behavior of tobacco tonoplasts were studied. Three precautions were found to be important for the analysis of vacuolar hydrolases and of the tonoplast. (a) Purification of protoplasts in a Ficoll gradient was necessary to remove cell debris which contained contaminating hydrolases adsorbed from the fungal cell-wall-degrading enzyme preparation. (b) Hydrolase activities in the homogenates of the intact cells or the tissue used and of the purified protoplasts had to be compared to verify the absence of contaminating hydrolases in the protoplast preparation. (c) Vacuoles obtained from the protoplasts by an osmotic shock had to be purified from the lysate in a Ficoll gradient. Since the density of the central vacuole approximates that of the protoplasts, about a 10% contamination of the vacuolar preparation by surviving protoplasts could not be eliminated and had to be taken into account when the distribution of enzymes and of radioactivity was calculated.THE INTRACELLULAR ACTIVITIES OF THE FOLLOWING ACID HYDROLASES WERE PRIMARILY LOCALIZED IN THE VACUOLE OF TOBACCO CELLS: alpha-mannosidase, beta-N-acetylglucosaminidase, beta-fructosidase, nuclease, phosphatase, phosphodiesterase. A similar composition of acid hydrolases was found in vacuoles obtained from protoplasts of tulip petals. Proteinase, a hydrolase with low activity in tobacco cells and tulip petals and therefore difficult to localize unequivocally, was found to be vacuolar in pineapple leaves, a tissue containing high levels of this enzyme. Our data support the hypothesis that the central vacuole of higher plant cells has an enzyme composition analogous to that of the animal lysosome.None of the vacuolar enzymes investigated was found to be bound to the tonoplast. When vacuoles were isolated from cells labeled with radioactive choline, the vacuolar

  20. Hepatitis B surface antigen (HBsAg) expression in plant cell culture: Kinetics of antigen accumulation in batch culture and its intracellular form.

    Science.gov (United States)

    Smith, Mark L; Mason, Hugh S; Shuler, Michael L

    2002-12-30

    The production of edible vaccines in transgenic plants and plant cell culture may be improved through a better understanding of antigen processing and assembly. The hepatitis B surface antigen (HBsAg) was chosen for study because it undergoes substantial and complex post-translational modifications, which are necessary for its immunogenicity. This antigen was expressed in soybean (Glycine max L. Merr. cv Williams 82) and tobacco NT1 (Nicotiana tabacum L.) cell suspension cultures, and HBsAg production in batch culture was characterized. The plant-derived antigen consisted predominantly of disulfide cross-linked HBsAg protein (p24(s)) dimers, which were all membrane associated. Similar to yeast, the plant-expressed HBsAg was retained intracellularly. The maximal HBsAg titers were obtained with soybean suspension cultures (20-22 mg/L) with titers in tobacco cultures being approximately 10-fold lower. For soybean cells, electron microscopy and immunolocalization demonstrated that all the HBsAg was localized to the endoplasmic reticulum (ER) and provoked dilation and proliferation of the ER network. Sucrose gradient analysis of crude extracts showed that HBsAg had a complex size distribution uncharacteristic of the antigen's normal structure of uniform 22-nm virus-like particles. The extent of authentic epitope formation was assessed by comparing total p24(s) synthesized to that reactive by polyclonal and monoclonal immunoassays. Depending on culture age, between 40% and 100% of total p24(s) was polyclonal antibody reactive whereas between 6% and 37% was recognized by a commercial monoclonal antibody assay. Possible strategies to increase HBsAg production and improve post-translational processing are discussed. Copyright 2002 Wiley Periodicals, Inc.

  1. Effects of granulocyte-macrophage colony-stimulating factor and interleukin 6 on the growth of leukemic blasts in suspension culture.

    Science.gov (United States)

    Tsao, C J; Cheng, T Y; Chang, S L; Su, W J; Tseng, J Y

    1992-05-01

    We examined the stimulatory effects of recombinant human granulocyte-macrophage colony-stimulating factor (GM-CSF) and interleukin 6 (IL)-6 on the in vitro proliferation of leukemic blast cells from patients with acute leukemia. Bone marrow or peripheral blood leukemic blast cells were obtained from 21 patients, including 14 cases of acute myeloblastic leukemia (AML), four cases of acute lymphoblastic leukemia (ALL), two cases of acute undifferentiated leukemia, and one case of acute mixed-lineage leukemia. The proliferation of leukemic blast cells was evaluated by measuring the incorporation of 3H-thymidine into cells incubated with various concentrations of cytokines for 3 days. GM-CSF stimulated the DNA synthesis (with greater than 2.0 stimulation index) of blast cells in 9 of 14 (64%) AML cases, two cases of acute undifferentiated leukemia and one case of acute mixed-lineage leukemia. Only two cases of AML blasts responded to IL-6 to grow in the short-term suspension cultures. GM-CSF and IL-6 did not display a synergistic effect on the growth of leukemic cells. Moreover, GM-CSF and IL-6 did not stimulate the proliferation of ALL blast cells. Binding study also revealed the specific binding of GM-CSF on the blast cells of acute undifferentiated leukemia and acute mixed-lineage leukemia. Our results indicated that leukemic blast cells of acute undifferentiated leukemia and acute mixed-lineage leukemia possessed functional GM-CSF receptors.

  2. Biomass Yield and Steviol Glycoside Production in Callus and Suspension Culture of Stevia rebaudiana Treated with Proline and Polyethylene Glycol.

    Science.gov (United States)

    Gupta, Pratibha; Sharma, Satyawati; Saxena, Sanjay

    2015-06-01

    Enhanced production of steviol glycosides (SGs) was observed in callus and suspension culture of Stevia rebaudiana treated with proline and polyethylene glycol (PEG). To study their effect, yellow-green and compact calli obtained from in vitro raised Stevia leaves were sub-cultured on MS medium supplemented with 2.0 mg l(-1) NAA and different concentrations of proline (2.5-10 mM) and PEG (2.5-10 %) for 2 weeks, and incubated at 24 ± 1 °C and 22.4 μmol m(-2) s(-1) light intensity provided by white fluorescent tubes for 16 h. Callus and suspension culture biomass (i.e. both fresh and dry weight content) was increased with 5 mM proline and 5 % PEG, while at further higher concentrations, they got reduced. Further, quantification of SGs content in callus (collected at 15th day) and suspension culture (collected at 10th and 15th day) treated with and without elicitors was analysed by HPLC. It was observed that chemical stress enhanced the production of SGs significantly. In callus, the content of SGs increased from 0.27 (control) to 1.09 and 1.83 % with 7.5 mM proline and 5 % PEG, respectively, which was about 4.0 and 7.0 times higher than control. However, in the case of suspension culture, the same concentrations of proline and polyethylene glycol enhanced the SG content from 1.36 (control) to 5.03 and 6.38 %, respectively, on 10th day which were 3.7 times and 4.7 times higher than control.

  3. Studies on the biosynthesis of lignins and their production in plant cell cultures. [Forsythia intermedia; Podophyllum hexandrum; Podophyllum peltatum

    Energy Technology Data Exchange (ETDEWEB)

    Abdul-Rahman, M.M.

    1988-01-01

    Phytochemical analysis of Forsythia intermedia tissues has demonstrated the presence of lignins of the dibenzylbutyrolactone and dioxabicyclo(3,3,0)octane classes, together with their O-glucosides. Lignin distribution in different parts of the part, and variation with the season has been recorded. Cell suspension cultures from F. intermedia were developed. These also synthesized lignins, though not the full range as found in the fresh tissues. Culture lines synthesizing either matairesinol 4{prime}-O-glucoside and major lignin components were established. These cultures rapidly metabolized exogenous lignins without producing detectable lignin transformation products. The seasonal variation in aryltetralin lactone levels in young plants Podophyllum hexandrum and P. peltatum has been investigated. Cell cultures of the plants were established, but no lignins were detectable in them. However, a protocol for micropropagation via embryoid production was obtained. Feeding experiments in P. hexandrum plants showed that matairesinol was a precursor of both podophyllotoxin and 4{prime}-demethylpodophyllotoxin, thus indicating it to be a common precursor of the trimethoxy and hydroxydimethoxy series of lignins in this plant. Precursor feeding experiments with {sup 3}H/{sup 14}C-labeled coniferyl alcohol showed an unexpected increase in {sup 3}H/{sup 14}C ratio when incorporated into both Forsythia and Podophyllum lignins.

  4. Plant cell walls to ethanol.

    Science.gov (United States)

    Conversion of plant cell walls to ethanol constitutes generation 2 bioethanol production. The process consists of several steps: biomass selection/genetic modification, physiochemical pretreatment, enzymatic saccharification, fermentation, and separation. Ultimately, it is desired to combine as man...

  5. Interaction of amatoxins with plant cells and RNA polymerases II: selection of amanitin-resistant cell lines and synthesis of amanitin-based affinity ligands

    International Nuclear Information System (INIS)

    Little, M.C.

    1984-01-01

    A series of experiments directed toward deriving basic information regarding plant RNA polymerase II is presented. The experiments described relate to the potential of isolating RNA polymerase II mutants in plants, using carrot cell cultures as models. Additionally, the synthesis of amanitin-based affinity ligands to immobilize isolated plant RNA polymerase II and associated transcriptional complexes is described. RNA polymerase II activities have been isolated from suspension cultures of carrot and compared to other plant RNA polymerases II with respect to subunit analysis and inhibition with α-amanitin. RNA polymerase II purified by polymin P absorption, DE52, phosphocellulose, and RNA-agarose chromatography is shown to copurify with proteins of 175 (and 200), 135, 70, 43, 28, 22, and 17 kdaltons apparent molecular weights. Conditions for accurate determination of amanitin inhibition of the enzyme are established using 3 H-amanitin and are presented for the first time for plant RNA polymerase II; RNA polymerase II from these cultures is shown to be inhibited by 50% at 3-5 nM by α-amanitin, a value 10-50 times lower than previously reported

  6. Cellular Molecular Changes in Nerium oleander (L.) Cell Culture Under Gamma Radiation Stress

    International Nuclear Information System (INIS)

    Salama, I.M.; Abd EL-Megid, M.H.M.

    2017-01-01

    This study was done to analyze the relationship between the various effects of five different doses of gamma ray treatments (control, 0, 100, 200, 300 and 400 rad) on cell suspension culture of Nerium oleander belonging to the family Apocynaceae, Plant samples were collected from Egyptian flora. The five treatments of the plants were characterized by analyzing variability in frozen biomass cell suspension culture of N. oleander through SDS PAGE and peroxidase is ozymes. The electrophorogram showed a total of 36 bands of proteins with molecular weight ranging from 10 to 225 KDa. The protein diversity analysis was done based on the presence or the absence of bands trhus interpreting their relevance. The his togram analysis clearly showed a high degree of diversity a long these five treatments of the plant. The results of electrophoretic patterns of peroxidase is ozymes that was extracted from frozen biomass cell suspension cultures after receiving the different gamma doses revealed remarkable molecular changes in all treatments. These changes in peroxidase isozymes and protein bands indicate the effect of the different irradiation treatments on the gene expiration

  7. Suspension-cultured BY-2 tobacco cells produce and mature immunologically active house dust mite allergens

    NARCIS (Netherlands)

    Lienard, David; Tran Dinh, Olivia; van Oort, Erika; van Overtvelt, Laurence; Bonneau, Caroline; Wambre, Eric; Bardor, Muriel; Cosette, Pascal; Didier-Laurent, Alain; de Borne, François Dorlhac; Delon, Rene; van Ree, Ronald; Moingeon, Philippe; Faye, Loïc; Gomord, Véronique

    2007-01-01

    The replacement of crude allergen extracts by selected allergens currently represents a major goal for the improvement of allergy diagnosis and immunotherapy. Indeed, the development of molecularly defined vaccines would facilitate both standardization and enhance batch-to-batch reproducibility as

  8. Structural characterisation of galactoglucomannan secreted by suspension-cultured cells of Nicotiana plumbaginifolia.

    Science.gov (United States)

    Sims, I M; Craik, D J; Bacic, A

    1997-08-25

    Galactoglucomannan (GGM) from cultures of Nicotiana plumbaginifolia has Man:Glc:Gal:Ara:Xyl in 1.0:1.1:1.0:0.1:0.04 ratio. Linkage analysis contained 4- and 4,6-Manp, 4-Glcp, terminal Galp and 2-Galp, small amounts and terminal Arap and terminal Xylp, and approximately 0.03 mol acetyl per mol of glucosyl residue. Treatment with alpha- and beta-D-galactosidases showed that the majority of the side-chains were either single Galp-alpha-(1-->residues or the disaccharide Galp-beta-(1-->2)-Galp-alpha-(1-->linked to O-6 of the 4-Manp residues of the glucomannan backbone. Analysis of the oligosaccharides generated by endo-(1-->4)-beta-mannanase digestion confirmed that the GGM comprises a backbone of predominantly alternating-->4)-D-Manp-beta-(1-->and-->4)-D-Glcp-beta-(1-->branch ed at O-6 of 65% of the 4-Manp residues. The major oligosaccharide identified was D-Glcp-beta-(1-->4)-[D-Galp-beta-(1-->2)-D-Galp-alpha-(1-->6)]-D-Man p-beta-(1-->4)-D-Glcp-beta-(1-->4)-[D-Galp-alpha-(1-->6)]-D-Manp -beta-(1-->(27%), and most of the other oligosaccharides produced in significant quantities were based on this structure.

  9. Characterization of transmembrane auxin transport in Arabidopsis suspension-cultured cells

    Czech Academy of Sciences Publication Activity Database

    Seifertová, Daniela; Skůpa, Petr; Rychtář, J.; Laňková, Martina; Pařezová, Markéta; Dobrev, Petre; Hoyerová, Klára; Petrášek, Jan; Zažímalová, Eva

    2014-01-01

    Roč. 171, č. 6 (2014), s. 429-437 ISSN 0176-1617 R&D Projects: GA ČR(CZ) GAP305/11/0797 Institutional support: RVO:61389030 Keywords : Auxin influx * Auxin efflux * Auxin metabolic profiling Subject RIV: EB - Genetics ; Molecular Biology Impact factor: 2.557, year: 2014

  10. Releasing intracellular product to prepare whole cell biocatalyst for biosynthesis of Monascus pigments in water-edible oil two-phase system.

    Science.gov (United States)

    Hu, Minglue; Zhang, Xuehong; Wang, Zhilong

    2016-11-01

    Selective releasing intracellular product in Triton X-100 micelle aqueous solution to prepare whole cell biocatalyst is a novel strategy for biosynthesis of Monascus pigments, in which cell suspension culture exhibits some advantages comparing with the corresponding growing cell submerged culture. In the present work, the nonionic surfactant Triton X-100 was successfully replaced by edible plant oils for releasing intracellular Monascus pigments. High concentration of Monascus pigments (with absorbance nearly 710 AU at 470 nm in the oil phase, normalized to the aqueous phase volume approximately 142 AU) was achieved by cell suspension culture in peanut oil-water two-phase system. Furthermore, the utilization of edible oil as extractant also fulfills the demand for application of Monascus pigments as natural food colorant.

  11. MUCUNA PRURIENS - IMPROVEMENT OF THE BIOTECHNOLOGICAL PRODUCTION OF THE ANTI-PARKINSON DRUG L-DOPA BY PLANT-CELL SELECTION

    NARCIS (Netherlands)

    PRAS, N; WOERDENBAG, HJ; BATTERMAN, S; VISSER, JF; VANUDEN, W

    1993-01-01

    Routinely grown cell suspension cultures of Mucuna pruriens L. (Fabaceae) were able to endogenously accumulate the anti-Parkinson drug L-dihydroxyphenylalanine (L-dopa) in the range between 0.2 and 2% on a dry weight (DW) basis. The green colour that developed in light-exposed cultures, appeared to

  12. Osmotic potential of Zinnia elegans plant material affects the yield ...

    African Journals Online (AJOL)

    Jane

    2010-12-20

    Dec 20, 2010 ... The Zinnia elegans cell suspension culture is excellent for ... development and therefore dimensions of TEs in an in vitro .... Electrical conductivity and light intensity effects on ..... cell wall formation in the woody dicot stem.

  13. Stem cells: a plant biology perspective

    NARCIS (Netherlands)

    Scheres, B.J.G.

    2005-01-01

    A recent meeting at the Juan March Foundation in Madrid, Spain brought together plant biologists to discuss the characteristics of plant stem cells that are unique and those that are shared by stem cells from the animal kingdom

  14. Regulation of Water in Plant Cells

    Science.gov (United States)

    Kowles, Richard V.

    2010-01-01

    Cell water relationships are important topics to be included in cell biology courses. Differences exist in the control of water relationships in plant cells relative to control in animal cells. One important reason for these differences is that turgor pressure is a consideration in plant cells. Diffusion and osmosis are the underlying factors…

  15. Enhanced production of L-DOPA in cell cultures of Mucuna pruriens L. and Mucuna prurita H.

    Science.gov (United States)

    Raghavendra, S; Kumar, V; Ramesh, C K; Khan, M H Moinuddin

    2012-01-01

    A comparative study on the production of 3,4-dihydroxyphenylalanine (L-DOPA) was carried out in cell cultures of two Mucuna species by elicitor treatment and precursor feeding. The influence of elicitors and the precursor molecule on L-DOPA production, polyphenol oxidase (PPO) and tyrosinase activities was also studied. Callus cultures were initiated in Mucuna pruriens L. and Mucuna prurita H. on MS medium supplemented with BAP and IAA at different concentrations. Suspension cultures were established in MS liquid medium supplemented with BAP, IAA, the elicitors methyl jasmonate, chitin and pectin or the precursor L-tyrosine at different concentrations for L-DOPA production. Compared to the controls, several-fold increases in L-DOPA concentration were observed in elicitor-treated and precursor-fed suspension cultures of both plant species. L-DOPA concentrations were comparatively higher in precursor-fed cultures than those receiving elicitor treatments. A parallel increase in tyrosinase and PPO levels was also observed. Loss of cell viability was observed at high concentrations of elicitor-treated cultures, whereas L-tyrosine did not cause any cell death. Compared to elicitor treatments, precursor feeding resulted in higher concentrations of L-DOPA production and tyrosinase activity. The efficacy of L-DOPA production was found to be higher for suspension cultures of M. pruriens compared to M. prurita in all treatments.

  16. Induction of high mitotic index in Petunia suspension cultures by sequential treatment with aphidicolin and colchicine.

    Science.gov (United States)

    Guri, A; Zelcer, A; Izhar, S

    1984-12-01

    Significantly higher than normal mitotic index (MI) values were induced in Petunia cell suspensions following treatments with colchicine, aphidicolin, drastic medium replacement, or a sequential application of aphidicolin and colchicine. This last treatment yielded the highest MI values: cells incubated with 30 μg/ml aphidicolin for 18 h, then cultured in drug-free medium for 8 h and finally exposed to 0.1% colchicine for 8 additional hours exhibited MI of 62.8% and 65.7% respectively, for the two cell lines in study.

  17. Scaled-up manufacturing of recombinant antibodies produced by plant cells in a 200-L orbitally-shaken disposable bioreactor.

    Science.gov (United States)

    Raven, Nicole; Rasche, Stefan; Kuehn, Christoph; Anderlei, Tibor; Klöckner, Wolf; Schuster, Flora; Henquet, Maurice; Bosch, Dirk; Büchs, Jochen; Fischer, Rainer; Schillberg, Stefan

    2015-02-01

    Tobacco BY-2 cells have emerged as a promising platform for the manufacture of biopharmaceutical proteins, offering efficient protein secretion, favourable growth characteristics and cultivation in containment under a controlled environment. The cultivation of BY-2 cells in disposable bioreactors is a useful alternative to conventional stainless steel stirred-tank reactors, and orbitally-shaken bioreactors could provide further advantages such as simple bag geometry, scalability and predictable process settings. We carried out a scale-up study, using a 200-L orbitally-shaken bioreactor holding disposable bags, and BY-2 cells producing the human monoclonal antibody M12. We found that cell growth and recombinant protein accumulation were comparable to standard shake flask cultivation, despite a 200-fold difference in cultivation volume. Final cell fresh weights of 300-387 g/L and M12 yields of ∼20 mg/L were achieved with both cultivation methods. Furthermore, we established an efficient downstream process for the recovery of M12 from the culture broth. The viscous spent medium prevented clarification using filtration devices, but we used expanded bed adsorption (EBA) chromatography with SP Sepharose as an alternative for the efficient capture of the M12 antibody. EBA was introduced as an initial purification step prior to protein A affinity chromatography, resulting in an overall M12 recovery of 75-85% and a purity of >95%. Our results demonstrate the suitability of orbitally-shaken bioreactors for the scaled-up cultivation of plant cell suspension cultures and provide a strategy for the efficient purification of antibodies from the BY-2 culture medium. © 2014 Wiley Periodicals, Inc.

  18. [Genetic regulation of plant shoot stem cells].

    Science.gov (United States)

    Al'bert, E V; Ezhova, T A

    2013-02-01

    This article describes the main features of plant stem cells and summarizes the results of studies of the genetic control of stem cell maintenance in the apical meristem of the shoot. It is demonstrated that the WUS-CLV gene system plays a key role in the maintenance of shoot apical stem cells and the formation of adventitious buds and somatic embryos. Unconventional concepts of plant stem cells are considered.

  19. Permanganate Fixation of Plant Cells

    Science.gov (United States)

    Mollenhauer, Hilton H.

    1959-01-01

    In an evaluation of procedures explored to circumvent some of the problems of osmium tetroxide-fixation and methacrylate embedding of plant materials, excised segments of root tips of Zea mays were fixed for electron microscopy in potassium permanganate in the following treatment variations: unbuffered and veronal-acetate buffered solutions of 0.6, 2.0, and 5.0 per cent KMnO4 at pH 5.0, 6.0, 6.7, and 7.5, and temperatures of 2–4°C. and 22°C. After fixation the segments were dehydrated, embedded in epoxy resin, sectioned, and observed or photographed. The cells of the central region of the rootcap are described. The fixation procedures employing unbuffered solutions containing 2.0 to 5.0 per cent KMnO4 at a temperature of 22°C. gave particularly good preservation of cell structure and all membrane systems. Similar results were obtained using a solution containing 2.0 per cent KMnO4, buffered with veronal-acetate to pH 6.0, and a fixation time of 2 hours at 22°C. The fixation procedure utilizing veronal-acetate buffered, 0.6 per cent KMnO4 at 2–4°C. and pH 6.7 also gave relatively good preservation of most cellular constituents. However, preservation of the plasma membrane was not so good, nor was the intensity of staining so great, as that with the group of fixatives containing greater concentrations of KMnO4. The other fixation procedures did not give satisfactory preservation of fine structure. A comparison is made of cell structures as fixed in KMnO4 or OsO4. PMID:14423414

  20. Quinoline Alkaloids in Suspension Cultures of Cinchona ledgeriana Treated with Various Substances

    Directory of Open Access Journals (Sweden)

    DIAH RATNADEWI

    2010-12-01

    Full Text Available Cinchona alkaloids are in extensive uses, not only for drugs but also for soft drink industries. They are harvested from the bark of trees Cinchona spp. after certain ages and therefore are available over a limited time. Cell culture is an alternative way to continuously produce such secondary metabolites in a much shorter time. Various substances were added in the normal growth media to promote quinoline alkaloids production by cell cultures of Cinchona ledgeriana. At the sixth week of culture, quinine and cinchonine contents were suppressed by paclobutrazol (PBZ, abscisic acid (ABA, or even by precursor tryptophan, while cinchonidine content was enhanced by 0.2 mg/l tryptophan to 43 fold of that produced by untreated cells (2.8% dry weight. At the seventh week of culture, the production of quinine and quinidine started to grow whereas the production of cinchonine and cinchonidine tended to decrease. An addition of 5 mg/l PBZ to culture media yielded the highest level of total quinine/quinidine after seven weeks, e.g. quinine 11 times more abundant and quinidine 23 fold higher compared to the untreated cells. Particularly the level of quinine which is the most demanded for medical and industrial purposes still need to be improved to approach to or even higher than that of extracted from the conventional source.

  1. Morphological classification of plant cell deaths

    NARCIS (Netherlands)

    Doorn, van W.G.; Beers, E.P.; Dangl, J.L.; Franklin-Tong, V.E.; Woltering, E.J.

    2011-01-01

    Programmed cell death (PCD) is an integral part of plant development and of responses to abiotic stress or pathogens. Although the morphology of plant PCD is, in some cases, well characterised and molecular mechanisms controlling plant PCD are beginning to emerge, there is still confusion about the

  2. Methyl Jasmonate and Salicylic Acid Induced Oxidative Stress and Accumulation of Phenolics in Panax ginseng Bioreactor Root Suspension Cultures

    Directory of Open Access Journals (Sweden)

    Kee-Yoeup Paek

    2007-03-01

    Full Text Available To investigate the enzyme variations responsible for the synthesis of phenolics, 40 day-old adventitious roots of Panax ginseng were treated with 200 μM methyl jasmonate (MJ or salicylic acid (SA in a 5 L bioreactor suspension culture (working volume 4 L. Both treatments caused an increase in the carbonyl and hydrogen peroxide (H2O2 contents, although the levels were lower in SA treated roots. Total phenolic, flavonoid, ascorbic acid, non-protein thiol (NPSH and cysteine contents and 1,1-diphenyl-2-picrylhydrazyl (DPPH radical reducing activity were increased by MJ and SA. Fresh weight (FW and dry weight (DW decreased significantly after 9 days of exposure to SA and MJ. The highest total phenolics (62%, DPPH activity (40%, flavonoids (88%, ascorbic acid (55%, NPSH (33%, and cysteine (62% contents compared to control were obtained after 9 days in SA treated roots. The activities of glucose 6-phosphate dehydrogenase, phenylalanine ammonia lyase, substrate specific peroxidases (caffeic acid peroxidase, quercetin peroxidase and ferulic acid peroxidase were higher in MJ treated roots than the SA treated ones. Increased shikimate dehydrogenase, chlorogenic acid peroxidase and β-glucosidase activities and proline content were observed in SA treated roots than in MJ ones. Cinnamyl alcohol dehydrogenase activity remained unaffected by both MJ and SA. These results strongly indicate that MJ and SA induce the accumulation of phenolic compounds in ginseng root by altering the phenolic synthesis enzymes.

  3. Cell fusion and nuclear fusion in plants.

    Science.gov (United States)

    Maruyama, Daisuke; Ohtsu, Mina; Higashiyama, Tetsuya

    2016-12-01

    Eukaryotic cells are surrounded by a plasma membrane and have a large nucleus containing the genomic DNA, which is enclosed by a nuclear envelope consisting of the outer and inner nuclear membranes. Although these membranes maintain the identity of cells, they sometimes fuse to each other, such as to produce a zygote during sexual reproduction or to give rise to other characteristically polyploid tissues. Recent studies have demonstrated that the mechanisms of plasma membrane or nuclear membrane fusion in plants are shared to some extent with those of yeasts and animals, despite the unique features of plant cells including thick cell walls and intercellular connections. Here, we summarize the key factors in the fusion of these membranes during plant reproduction, and also focus on "non-gametic cell fusion," which was thought to be rare in plant tissue, in which each cell is separated by a cell wall. Copyright © 2016 Elsevier Ltd. All rights reserved.

  4. Pathological modifications of plant stem cell destiny

    Science.gov (United States)

    In higher plants, the shoot apex contains undifferentiated stem cells that give rise to various tissues and organs. The fate of these stem cells determines the pattern of plant growth as well as reproduction; and such fate is genetically preprogrammed. We found that a bacterial infection can derai...

  5. Microtubule networks for plant cell division

    NARCIS (Netherlands)

    Keijzer, de Jeroen; Mulder, B.M.; Janson, M.E.

    2014-01-01

    During cytokinesis the cytoplasm of a cell is divided to form two daughter cells. In animal cells, the existing plasma membrane is first constricted and then abscised to generate two individual plasma membranes. Plant cells on the other hand divide by forming an interior dividing wall, the so-called

  6. Hydroquinone: O-glucosyltransferase from cultivated Rauvolfia cells: enrichment and partial amino acid sequences.

    Science.gov (United States)

    Arend, J; Warzecha, H; Stöckigt, J

    2000-01-01

    Plant cell suspension cultures of Rauvolfia are able to produce a high amount of arbutin by glucosylation of exogenously added hydroquinone. A four step purification procedure using anion exchange, hydrophobic interaction, hydroxyapatite-chromatography and chromatofocusing delivered in a yield of 0.5%, an approximately 390 fold enrichment of the involved glucosyltransferase. SDS-PAGE showed a M(r) for the enzyme of 52 kDa. Proteolysis of the pure enzyme with endoproteinase LysC revealed six peptide fragments with 9-23 amino acids which were sequenced. Sequence alignment of the six peptides showed high homologies to glycosyltransferases from other higher plants.

  7. Hydrolytic enzymes in the central vacuole of plant cells

    International Nuclear Information System (INIS)

    Boller, T.; Kende, H.

    1979-01-01

    The hydrolase content of vacuoles isolated from protoplasts of suspension-cultured tobacco cells, of tulip petals, and pineapple leaves, and the sedimentation behavior of tobacco tonoplasts were studied. Three precautions were found to be important for the analysis of vacuolar hydrolases and of the tonoplast: (a) purification of protoplasts in a Ficoll gradient was necessary to remove cell debris which contained contaminating hydrolases adsorbed from the fungal cell-wall-degrading enzyme preparation; (b) hydrolase activities in the homogenates of the intact cells or the tissue used and of the purified protoplasts had to be compared to verify the absence of contaminating hydrolases in the protoplast preparation; and (c) vacuoles obtained from the protoplasts by an osmotic shock had to be purified from the lysate in a Ficoll gradient. Since the density of the central vacuole approximates that of the protoplasts, about a 10% contamination of the vacuolar preparation by surviving protoplasts could not be eliminated. The intracellular activities of the following acid hydrolases were primarily localized in the vacuole of tobacco cells: α-mannosidase, β-N-acetylglucosaminidase, β-fructosidase, nuclease, phosphatase, phosphodiesterase. A similar composition of acid hydrolases was found in vacuoles obtained from protoplasts of tulip petals. Proteinase, a hydrolase with low activity in tobacco cells and tulip petals was found to be vacuolar in pineapple leaves, a tissue containing high levels of this enzyme. None of the vacuolar enzymes investigated ws found to be bound to the tonoplast. When vacuoles were isolated from cells labeled with radioactive choline, the vacuolar membrane was found to contain radioactivity. On sucrose gradients, the label incorporated into tonoplasts banded around a density of 1.10 grams per cubic centimeter

  8. Enzymatic Modification of Plant Cell Wall Polysaccharides

    DEFF Research Database (Denmark)

    Øbro, Jens; Hayashi, Takahisa; Mikkelsen, Jørn Dalgaard

    2011-01-01

    Plant cell walls are intricate structures with remarkable properties, widely used in almost every aspect of our life. Cell walls consist largely of complex polysaccharides and there is often a need for chemical and biochemical processing before industrial use. There is an increasing demand...... for sustainable processes that replace chemical treatments with white biotechnology. Plants can contribute significantly to this sustainable process by producing plant or microbialenzymes in planta that are necessary for plant cell wall modification or total degradation. This will give rise to superior food...... fibres, hydrocolloids, paper,textile, animal feeds or biofuels. Classical microbial-based fermentation systems could in the future face serious competition from plant-based expression systems for enzyme production. Plant expressed enzymes can either be targeted to specific cellular compartments...

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

    Science.gov (United States)

    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.

  10. Stress Response Monitoring of Photoautotrophic Higher Plant Suspension Cultures by Fluorescence Imaging for High-Throughput Toxic Compound Screening

    Czech Academy of Sciences Publication Activity Database

    Segečová, Anna; Červený, Jan; Roitsch, Thomas

    2017-01-01

    Roč. 8, č. 6 (2017), s. 678-692 ISSN 2152-2197 R&D Projects: GA MŠk(CZ) LO1415; GA ČR(CZ) GA15-17367S; GA MŠk(CZ) LM2015055 Institutional support: RVO:67179843 Keywords : Toxins * Toxicants * Ecotoxicology * PAM Chlorophyll Fluorescence Subject RIV: CE - Biochemistry OBOR OECD: Biochemistry and molecular biology

  11. Plant cell wall polysaccharide analysis during cell elongation

    DEFF Research Database (Denmark)

    Guo, Xiaoyuan

    Plant cell walls are complex structures whose composition and architecture are important to various cellular activities. Plant cell elongation requires a high level of rearrangement of the cell wall polymers to enable cell expansion. However, the cell wall polysaccharides dynamics during plant cell...... elongation is poorly understood. This PhD project aims to elucidate the cell wall compositional and structural change during cell elongation by using Comprehensive Microarray Polymer Profiling (CoMPP), microscopic techniques and molecular modifications of cell wall polysaccharide. Developing cotton fibre......, pea and Arabidopsis thaliana were selected as research models to investigate different types of cell elongation, developmental elongation and tropism elongation. A set of comprehensive analysis covering 4 cotton species and 11 time points suggests that non-cellulosic polysaccharides contribute...

  12. Semi-synthetic preparation of 1-O-[1'-14C]hexadecyl-2-acetyl-sn-glycero-3-phosphocholine (platelet activating factor) using plant cell cultures

    International Nuclear Information System (INIS)

    Weber, N.; Mangold, H.K.

    1985-01-01

    Incubation of photomixotrophic cell suspension cultures of rape (Brassica napus) and heterotrophic cell suspension cultures of soya (Glycine max) with 1-O-[1'- 14 C]hexadecyl-sn-glycerol or rac-1-O-[1'- 14 C]hexadecylglycerol leads in high yield (up to 78%) to labeled 1-O-hexadecyl-2-acyl-sn-glycero-3-phosphocholines. Alkaline hydrolysis of the choline glycerophospholipids yields pure 1-O-[1'- 14 C]hexadecyl-sn-glycero-3-phosphocholine. 1-O-[1'-14C]Hexadecyl-2-acetyl-sn-glycero-3-phosphocholine (platelet activating factor) is obtained by acetylating the lyso compound. The semi-synthetic preparation described leads to labeled platelet activating factor in an overall yield of 50-60% without loss of specific activity

  13. Morphological classification of plant cell deaths.

    Science.gov (United States)

    van Doorn, W G; Beers, E P; Dangl, J L; Franklin-Tong, V E; Gallois, P; Hara-Nishimura, I; Jones, A M; Kawai-Yamada, M; Lam, E; Mundy, J; Mur, L A J; Petersen, M; Smertenko, A; Taliansky, M; Van Breusegem, F; Wolpert, T; Woltering, E; Zhivotovsky, B; Bozhkov, P V

    2011-08-01

    Programmed cell death (PCD) is an integral part of plant development and of responses to abiotic stress or pathogens. Although the morphology of plant PCD is, in some cases, well characterised and molecular mechanisms controlling plant PCD are beginning to emerge, there is still confusion about the classification of PCD in plants. Here we suggest a classification based on morphological criteria. According to this classification, the use of the term 'apoptosis' is not justified in plants, but at least two classes of PCD can be distinguished: vacuolar cell death and necrosis. During vacuolar cell death, the cell contents are removed by a combination of autophagy-like process and release of hydrolases from collapsed lytic vacuoles. Necrosis is characterised by early rupture of the plasma membrane, shrinkage of the protoplast and absence of vacuolar cell death features. Vacuolar cell death is common during tissue and organ formation and elimination, whereas necrosis is typically found under abiotic stress. Some examples of plant PCD cannot be ascribed to either major class and are therefore classified as separate modalities. These are PCD associated with the hypersensitive response to biotrophic pathogens, which can express features of both necrosis and vacuolar cell death, PCD in starchy cereal endosperm and during self-incompatibility. The present classification is not static, but will be subject to further revision, especially when specific biochemical pathways are better defined.

  14. Toward stable genetic engineering of human o-glycosylation in plants

    DEFF Research Database (Denmark)

    Yang, Zhang; Bennett, Eric Paul; Jørgensen, Bodil

    2012-01-01

    Glycosylation is the most abundant and complex posttranslational modification to be considered for recombinant production of therapeutic proteins. Mucin-type (N-acetylgalactosamine [GalNAc]-type) O-glycosylation is found in eumetazoan cells but absent in plants and yeast, making these cell types...... an obvious choice for de novo engineering of this O-glycosylation pathway. We previously showed that transient implementation of O-glycosylation capacity in plants requires introduction of the synthesis of the donor substrate UDP-GalNAc and one or more polypeptide GalNAc-transferases for incorporating Gal......NAc residues into proteins. Here, we have stably engineered O-glycosylation capacity in two plant cell systems, soil-grown Arabidopsis (Arabidopsis thaliana) and tobacco (Nicotiana tabacum) Bright Yellow-2 suspension culture cells. Efficient GalNAc O-glycosylation of two stably coexpressed substrate O...

  15. Synthesis of plant cell wall oligosaccharides

    DEFF Research Database (Denmark)

    Clausen, Mads Hartvig

    Plant cell walls are structurally complex and contain a large number of diverse carbohydrate polymers. These plant fibers are a highly valuable bio-resource and the focus of food, energy and health research. We are interested in studying the interplay of plant cell wall carbohydrates with proteins...... for characterizing protein-carbohydrate binding. The presentation will highlight chemical syntheses of plant cell wall oligosaccharides from the group and provide examples from studies of their interactions with proteins....... such as enzymes, cell surface lectins, and antibodies. However, detailed molecular level investigations of such interactions are hampered by the heterogeneity and diversity of the polymers of interest. To circumvent this, we target well-defined oligosaccharides with representative structures that can be used...

  16. Disposable Bioreactors for Plant Micropropagation and Mass Plant Cell Culture

    Science.gov (United States)

    Ducos, Jean-Paul; Terrier, Bénédicte; Courtois, Didier

    Different types of bioreactors are used at Nestlé R&D Centre - Tours for mass propagation of selected plant varieties by somatic embryogenesis and for large scale culture of plants cells to produce metabolites or recombinant proteins. Recent studies have been directed to cut down the production costs of these two processes by developing disposable cell culture systems. Vegetative propagation of elite plant varieties is achieved through somatic embryogenesis in liquid medium. A pilot scale process has recently been set up for the industrial propagation of Coffea canephora (Robusta coffee). The current production capacity is 3.0 million embryos per year. The pre-germination of the embryos was previously conducted by temporary immersion in liquid medium in 10-L glass bioreactors. An improved process has been developed using a 10-L disposable bioreactor consisting of a bag containing a rigid plastic box ('Box-in-Bag' bioreactor), insuring, amongst other advantages, a higher light transmittance to the biomass due to its horizontal design. For large scale cell culture, two novel flexible plastic-based disposable bioreactors have been developed from 10 to 100 L working volumes, validated with several plant species ('Wave and Undertow' and 'Slug Bubble' bioreactors). The advantages and the limits of these new types of bioreactor are discussed, based mainly on our own experience on coffee somatic embryogenesis and mass cell culture of soya and tobacco.

  17. Food availability and reproduction affects lipid and fatty acid composition of the brown mussel, Perna perna, raised in suspension culture.

    Science.gov (United States)

    Narváez, Mirle; Freites, L; Guevara, M; Mendoza, J; Guderley, H; Lodeiros, C J; Salazar, G

    2008-02-01

    We examined the influence of the reproductive cycle and environmental factors on variations of the condition index (CI), tissue dry mass, shell size, total lipid content, and relative percent of fatty acids in the mussel, Perna perna. Spat or juveniles were reared to commercial size (70 mm) in suspension culture in the Golfo de Cariaco, Venezuela between May and October 2004. The dry mass of soft tissues and shell, a visual assessment of gonadal status and the organism lipid profile were established every fortnight. In parallel, we measured the environmental conditions, following chlorophyll a, salinity, temperature and seston levels. After an initial decrease, the CI rose and remained high until August after which it decreased continuously until October. Total lipid values also decreased initially, after which they showed two periods of rapid recuperation and depletion, the first between May and August and the second between August and October. Similar tendencies were noted in the fatty acids, C18:3n-3, C18:4n-3 and C22:6n-3. Correlation analysis found no significant relationships between environmental parameters and the variations in total lipids. However, significant correlations were noted between fatty acids and specific environmental parameters. In particular, temperature was inversely correlated with C14:0, C16:1n-7, C18:0, C18:1n-9 and 20:5n-3. Chlorophyll a was positively correlated with C14:0, C16:1n-7, C18:1n-7, C18:4n-3 and 20:4n-6. On the other hand, gametogenesis had an effect on C14:0, C16:1n-7, C18:1n-9 and C18:1n-7, while spawned and gonadal regression states had an effect on fatty acid 20:4n-6. Temperature and chlorophyll a levels strongly influenced the proportion of mussels spawning, suggesting that their influence upon lipid composition may be secondary to their impact upon reproduction. Despite the thermal stability of this tropical system, the lipid composition of mussels changed markedly during the study, reflecting the central role of diet

  18. Redox regulation of plant stem cell fate.

    Science.gov (United States)

    Zeng, Jian; Dong, Zhicheng; Wu, Haijun; Tian, Zhaoxia; Zhao, Zhong

    2017-10-02

    Despite the importance of stem cells in plant and animal development, the common mechanisms of stem cell maintenance in both systems have remained elusive. Recently, the importance of hydrogen peroxide (H 2 O 2 ) signaling in priming stem cell differentiation has been extensively studied in animals. Here, we show that different forms of reactive oxygen species (ROS) have antagonistic roles in plant stem cell regulation, which were established by distinct spatiotemporal patterns of ROS-metabolizing enzymes. The superoxide anion (O2·-) is markedly enriched in stem cells to activate WUSCHEL and maintain stemness, whereas H 2 O 2 is more abundant in the differentiating peripheral zone to promote stem cell differentiation. Moreover, H 2 O 2 negatively regulates O2·- biosynthesis in stem cells, and increasing H 2 O 2 levels or scavenging O2·- leads to the termination of stem cells. Our results provide a mechanistic framework for ROS-mediated control of plant stem cell fate and demonstrate that the balance between O2·- and H 2 O 2 is key to stem cell maintenance and differentiation. © 2017 The Authors.

  19. Morphological classification of plant cell deaths

    DEFF Research Database (Denmark)

    van Doorn, W.G.; Beers, E.P.; Dangl, J.L.

    2011-01-01

    , which can express features of both necrosis and vacuolar cell death, PCD in starchy cereal endosperm and during self-incompatibility. The present classification is not static, but will be subject to further revision, especially when specific biochemical pathways are better defined....... the classification of PCD in plants. Here we suggest a classification based on morphological criteria. According to this classification, the use of the term 'apoptosis' is not justified in plants, but at least two classes of PCD can be distinguished: vacuolar cell death and necrosis. During vacuolar cell death...

  20. Laser-mediated perforation of plant cells

    Science.gov (United States)

    Wehner, Martin; Jacobs, Philipp; Esser, Dominik; Schinkel, Helga; Schillberg, Stefan

    2007-07-01

    The functional analysis of plant cells at the cellular and subcellular levels requires novel technologies for the directed manipulation of individual cells. Lasers are increasingly exploited for the manipulation of plant cells, enabling the study of biological processes on a subcellular scale including transformation to generate genetically modified plants. In our setup either a picosecond laser operating at 1064 nm wavelength or a continuous wave laser diode emitting at 405 nm are coupled into an inverse microscope. The beams are focused to a spot size of about 1.5 μm and the tobacco cell protoplasts are irradiated. Optoporation is achieved when targeting the laser focal spot at the outermost edge of the plasma membrane. In case of the picosecond laser a single pulse with energy of about 0.4 μJ was sufficient to perforate the plasma membrane enabling the uptake of dye or DNA from the surrounding medium into the cytosol. When the ultraviolet laser diode at a power level of 17 mW is employed an irradiation time of 200 - 500 milliseconds is necessary to enable the uptake of macromolecules. In the presence of an EYFP encoding plasmid with a C-terminal peroxisomal signal sequence in the surrounding medium transient transformation of tobacco protoplasts could be achieved in up to 2% of the optoporated cells. Single cell perforation using this novel optoporation method shows that isolated plant cells can be permeabilized without direct manipulation. This is a valuable procedure for cell-specific applications, particularly where the import of specific molecules into plant cells is required for functional analysis.

  1. UV-Induced Cell Death in Plants

    Science.gov (United States)

    Nawkar, Ganesh M.; Maibam, Punyakishore; Park, Jung Hoon; Sahi, Vaidurya Pratap; Lee, Sang Yeol; Kang, Chang Ho

    2013-01-01

    Plants are photosynthetic organisms that depend on sunlight for energy. Plants respond to light through different photoreceptors and show photomorphogenic development. Apart from Photosynthetically Active Radiation (PAR; 400–700 nm), plants are exposed to UV light, which is comprised of UV-C (below 280 nm), UV-B (280–320 nm) and UV-A (320–390 nm). The atmospheric ozone layer protects UV-C radiation from reaching earth while the UVR8 protein acts as a receptor for UV-B radiation. Low levels of UV-B exposure initiate signaling through UVR8 and induce secondary metabolite genes involved in protection against UV while higher dosages are very detrimental to plants. It has also been reported that genes involved in MAPK cascade help the plant in providing tolerance against UV radiation. The important targets of UV radiation in plant cells are DNA, lipids and proteins and also vital processes such as photosynthesis. Recent studies showed that, in response to UV radiation, mitochondria and chloroplasts produce a reactive oxygen species (ROS). Arabidopsis metacaspase-8 (AtMC8) is induced in response to oxidative stress caused by ROS, which acts downstream of the radical induced cell death (AtRCD1) gene making plants vulnerable to cell death. The studies on salicylic and jasmonic acid signaling mutants revealed that SA and JA regulate the ROS level and antagonize ROS mediated cell death. Recently, molecular studies have revealed genes involved in response to UV exposure, with respect to programmed cell death (PCD). PMID:23344059

  2. Osmosis in Poisoned Plant Cells.

    Science.gov (United States)

    Tatina, Robert

    1998-01-01

    Describes two simple laboratory exercises that allow students to test hypotheses concerning the requirement of cell energy for osmosis. The first exercise involves osmotically-caused changes in the length of potato tubers and requires detailed quantitative observations. The second exercise involves osmotically-caused changes in turgor of Elodea…

  3. Inducible cell death in plant immunity

    DEFF Research Database (Denmark)

    Hofius, Daniel; Tsitsigiannis, Dimitrios I; Jones, Jonathan D G

    2006-01-01

    Programmed cell death (PCD) occurs during vegetative and reproductive plant growth, as typified by autumnal leaf senescence and the terminal differentiation of the endosperm of cereals which provide our major source of food. PCD also occurs in response to environmental stress and pathogen attack......, and these inducible PCD forms are intensively studied due their experimental tractability. In general, evidence exists for plant cell death pathways which have similarities to the apoptotic, autophagic and necrotic forms described in yeast and metazoans. Recent research aiming to understand these pathways...

  4. An assay for secologanin in plant tissues based on enzymatic conversion into strictosidine

    DEFF Research Database (Denmark)

    Hallard, Didier; van der Heijden, Robert; Contin, Adriana

    1998-01-01

    strictosidine, a reaction catalysed by the enzyme strictosidine synthase (STR; E.C. 4.3.3.2). Subsequently, the formation of strictosidine is quantified by HPLC. STR was isolated from transgenic Nicotiana tabacum cells expressing a cDNA-derived gene coding for STR from Catharanthus roseus. The high specificity......The secoiridoid glucoside secologanin is the terpenoid building block in the biosynthesis of terpenoid indole alkaloids. A method for its determination in plant tissues and cell suspension cultures has been developed. This assay is based on the condensation of secologanin with tryptamine, yielding...... of STR for secologanin, in combination with a sensitive and selective HPLC system, allows a simple extraction of secologanin from plant tissue. The detection limit of this methos is 15 ng secologanin. Using this assay, secologanin contents were determined in tissues of various plant species; Lonicera...

  5. Mechanochemical Polarization of Contiguous Cell Walls Shapes Plant Pavement Cells.

    Science.gov (United States)

    Majda, Mateusz; Grones, Peter; Sintorn, Ida-Maria; Vain, Thomas; Milani, Pascale; Krupinski, Pawel; Zagórska-Marek, Beata; Viotti, Corrado; Jönsson, Henrik; Mellerowicz, Ewa J; Hamant, Olivier; Robert, Stéphanie

    2017-11-06

    The epidermis of aerial plant organs is thought to be limiting for growth, because it acts as a continuous load-bearing layer, resisting tension. Leaf epidermis contains jigsaw puzzle piece-shaped pavement cells whose shape has been proposed to be a result of subcellular variations in expansion rate that induce local buckling events. Paradoxically, such local compressive buckling should not occur given the tensile stresses across the epidermis. Using computational modeling, we show that the simplest scenario to explain pavement cell shapes within an epidermis under tension must involve mechanical wall heterogeneities across and along the anticlinal pavement cell walls between adjacent cells. Combining genetics, atomic force microscopy, and immunolabeling, we demonstrate that contiguous cell walls indeed exhibit hybrid mechanochemical properties. Such biochemical wall heterogeneities precede wall bending. Altogether, this provides a possible mechanism for the generation of complex plant cell shapes. Copyright © 2017 Elsevier Inc. All rights reserved.

  6. Improved method for HPLC analysis of polyamines, agmatine and aromatic monoamines in plant tissue

    Science.gov (United States)

    Slocum, R. D.; Flores, H. E.; Galston, A. W.; Weinstein, L. H.

    1989-01-01

    The high performance liquid chromatographic (HPLC) method of Flores and Galston (1982 Plant Physiol 69: 701) for the separation and quantitation of benzoylated polyamines in plant tissues has been widely adopted by other workers. However, due to previously unrecognized problems associated with the derivatization of agmatine, this important intermediate in plant polyamine metabolism cannot be quantitated using this method. Also, two polyamines, putrescine and diaminopropane, also are not well resolved using this method. A simple modification of the original HPLC procedure greatly improves the separation and quantitation of these amines, and further allows the simulation analysis of phenethylamine and tyramine, which are major monoamine constituents of tobacco and other plant tissues. We have used this modified HPLC method to characterize amine titers in suspension cultured carrot (Daucas carota L.) cells and tobacco (Nicotiana tabacum L.) leaf tissues.

  7. The Metabolic Fate of Deoxynivalenol and Its Acetylated Derivatives in a Wheat Suspension Culture: Identification and Detection of DON-15-O-Glucoside, 15-Acetyl-DON-3-O-Glucoside and 15-Acetyl-DON-3-Sulfate

    Directory of Open Access Journals (Sweden)

    Clemens Schmeitzl

    2015-08-01

    Full Text Available Deoxynivalenol (DON is a protein synthesis inhibitor produced by the Fusarium species, which frequently contaminates grains used for human or animal consumption. We treated a wheat suspension culture with DON or one of its acetylated derivatives, 3-acetyl-DON (3-ADON, 15-acetyl-DON (15-ADON and 3,15-diacetyl-DON (3,15-diADON, and monitored the metabolization over a course of 96 h. Supernatant and cell extract samples were analyzed using a tailored LC-MS/MS method for the quantification of DON metabolites. We report the formation of tentatively identified DON-15-O-β-D-glucoside (D15G and of 15-acetyl-DON-3-sulfate (15-ADON3S as novel deoxynivalenol metabolites in wheat. Furthermore, we found that the recently identified 15-acetyl-DON-3-O-β-D-glucoside (15-ADON3G is the major metabolite produced after 15-ADON challenge. 3-ADON treatment led to a higher intracellular content of toxic metabolites after six hours compared to all other treatments. 3-ADON was exclusively metabolized into DON before phase II reactions occurred. In contrast, we found that 15-ADON was directly converted into 15-ADON3G and 15-ADON3S in addition to metabolization into deoxynivalenol-3-O-β-D-glucoside (D3G. This study highlights significant differences in the metabolization of DON and its acetylated derivatives.

  8. Direct FuelCell/Turbine Power Plant

    Energy Technology Data Exchange (ETDEWEB)

    Hossein Ghezel-Ayagh

    2008-09-30

    This report summarizes the progress made in development of Direct FuelCell/Turbine (DFC/T{reg_sign}) power plants for generation of clean power at very high efficiencies. The DFC/T system employs an indirectly heated Turbine Generator to supplement fuel cell generated power. The concept extends the high efficiency of the fuel cell by utilizing the fuel cell's byproduct heat in a Brayton cycle. Features of the DFC/T system include: electrical efficiencies of up to 75% on natural gas, minimal emissions, reduced carbon dioxide release to the environment, simplicity in design, direct reforming internal to the fuel cell, and potential cost competitiveness with existing combined cycle power plants. Proof-of-concept tests using a sub-MW-class DFC/T power plant at FuelCell Energy's (FCE) Danbury facility were conducted to validate the feasibility of the concept and to measure its potential for electric power production. A 400 kW-class power plant test facility was designed and retrofitted to conduct the tests. The initial series of tests involved integration of a full-size (250 kW) Direct FuelCell stack with a 30 kW Capstone microturbine. The operational aspects of the hybrid system in relation to the integration of the microturbine with the fuel cell, process flow and thermal balances, and control strategies for power cycling of the system, were investigated. A subsequent series of tests included operation of the sub-MW Direct FuelCell/Turbine power plant with a Capstone C60 microturbine. The C60 microturbine extended the range of operation of the hybrid power plant to higher current densities (higher power) than achieved in initial tests using the 30kW microturbine. The proof-of-concept test results confirmed the stability and controllability of operating a fullsize (250 kW) fuel cell stack in combination with a microturbine. Thermal management of the system was confirmed and power plant operation, using the microturbine as the only source of fresh air supply

  9. Plant cells : immobilization and oxygen transfer

    NARCIS (Netherlands)

    Hulst, A.C.

    1987-01-01

    The study described in this thesis is part of the integrated project 'Biotechnological production of non-persistent bioinsecticides by means of plant cells invitro ' and was done in close cooperation with the research Institute Ital within the framework

  10. Plant Cell Culture Initiation: practical tips

    NARCIS (Netherlands)

    Hall, R.D.

    2001-01-01

    The use of cultured plant cells in either organized or unorganized form has increased vey considerably in the last 10-15 yr. Many new technologies have been developed and applications in both fundamental and applied research have led to the development of some powerful tools for improving our

  11. Glycoprotein component of plant cell walls

    International Nuclear Information System (INIS)

    Cooper, J.B.; Chen, J.A.; Varner, J.E.

    1984-01-01

    The primary wall surrounding most dicotyledonous plant cells contains a hydroxyproline-rich glycoprotein (HRGP) component named extensin. A small group of glycopeptides solubilized from isolated cell walls by proteolysis contained a repeated pentapeptide glycosylated by tri- and tetraarabinosides linked to hydroxyproline and, by galactose, linked to serine. Recently, two complementary approaches to this problem have provided results which greatly increase the understanding of wall extensin. In this paper the authors describe what is known about the structure of soluble extensin secreted into the walls of the carrot root cells

  12. Plant cells oxidize hydroxylamines to NO

    Science.gov (United States)

    Rümer, Stefan; Gupta, Kapuganti Jagadis; Kaiser, Werner M.

    2009-01-01

    Plants are known to produce NO via the reduction of nitrite. Oxidative NO production in plants has been considered only with respect to a nitric oxide synthase (NOS). Here it is shown that tobacco cell suspensions emitted NO when hydroxylamine (HA) or salicylhydroxamate (SHAM), a frequently used AOX inhibitor, was added. NG-hydroxy-L-arginine, a putative intermediate in the NOS-reaction, gave no NO emission. Only a minor fraction (≤1%) of the added HA or SHAM was emitted as NO. Production of NO was decreased by anoxia or by the addition of catalase, but was increased by conditions inducing reactive oxygen (ROS) or by the addition of hydrogen peroxide. Cell-free enzyme solutions generating superoxide or hydrogen peroxide also led to the formation of NO from HA or (with lower rates) from SHAM, and nitrite was also an oxidation product. Unexpectedly, the addition of superoxide dismutase (SOD) to cell suspensions stimulated NO formation from hydroxylamines, and SOD alone (without cells) also catalysed the production of NO from HA or SHAM. NO production by SOD plus HA was higher in nitrogen than in air, but from SOD plus SHAM it was lower in nitrogen. Thus, SOD-catalysed NO formation from SHAM and from HA may involve different mechanisms. While our data open a new possibility for oxidative NO formation in plants, the existence and role of these reactions under physiological conditions is not yet clear. PMID:19357430

  13. Diuretics Prime Plant Immunity in Arabidopsis thaliana

    Science.gov (United States)

    Noutoshi, Yoshiteru; Ikeda, Mika; Shirasu, Ken

    2012-01-01

    Plant activators are agrochemicals that activate the plant immune system, thereby enhancing disease resistance. Due to their prophylactic and durable effects on a wide spectrum of diseases, plant activators can provide synergistic crop protection when used in combination with traditional pest controls. Although plant activators have achieved great success in wet-rice farming practices in Asia, their use is still limited. To isolate novel plant activators applicable to other crops, we screened a chemical library using a method that can selectively identify immune-priming compounds. Here, we report the isolation and characterization of three diuretics, bumetanide, bendroflumethiazide and clopamide, as immune-priming compounds. These drugs upregulate the immunity-related cell death of Arabidopsis suspension-cultured cells induced with an avirulent strain of Pseudomonas syringae pv. tomato in a concentration-dependent manner. The application of these compounds to Arabidopsis plants confers disease resistance to not only the avirulent but also a virulent strain of the pathogen. Unlike salicylic acid, an endogenous phytohormone that governs disease resistance in response to biotrophic pathogens, the three diuretic compounds analyzed here do not induce PR1 or inhibit plant growth, showing potential as lead compounds in a practical application. PMID:23144763

  14. Characterization of Cellulose Synthesis in Plant Cells

    Directory of Open Access Journals (Sweden)

    Samaneh Sadat Maleki

    2016-01-01

    Full Text Available Cellulose is the most significant structural component of plant cell wall. Cellulose, polysaccharide containing repeated unbranched β (1-4 D-glucose units, is synthesized at the plasma membrane by the cellulose synthase complex (CSC from bacteria to plants. The CSC is involved in biosynthesis of cellulose microfibrils containing 18 cellulose synthase (CesA proteins. Macrofibrils can be formed with side by side arrangement of microfibrils. In addition, beside CesA, various proteins like the KORRIGAN, sucrose synthase, cytoskeletal components, and COBRA-like proteins have been involved in cellulose biosynthesis. Understanding the mechanisms of cellulose biosynthesis is of great importance not only for improving wood production in economically important forest trees to mankind but also for plant development. This review article covers the current knowledge about the cellulose biosynthesis-related gene family.

  15. Characterization of Cellulose Synthesis in Plant Cells

    Science.gov (United States)

    Maleki, Samaneh Sadat; Mohammadi, Kourosh; Ji, Kong-shu

    2016-01-01

    Cellulose is the most significant structural component of plant cell wall. Cellulose, polysaccharide containing repeated unbranched β (1-4) D-glucose units, is synthesized at the plasma membrane by the cellulose synthase complex (CSC) from bacteria to plants. The CSC is involved in biosynthesis of cellulose microfibrils containing 18 cellulose synthase (CesA) proteins. Macrofibrils can be formed with side by side arrangement of microfibrils. In addition, beside CesA, various proteins like the KORRIGAN, sucrose synthase, cytoskeletal components, and COBRA-like proteins have been involved in cellulose biosynthesis. Understanding the mechanisms of cellulose biosynthesis is of great importance not only for improving wood production in economically important forest trees to mankind but also for plant development. This review article covers the current knowledge about the cellulose biosynthesis-related gene family. PMID:27314060

  16. Arabidopsis ATP A2 peroxidase. Expression and high-resolution structure of a plant peroxidase with implications for lignification

    DEFF Research Database (Denmark)

    Ostergaard, L; Teilum, K; Mirza, O

    2000-01-01

    Lignins are phenolic biopolymers synthesized by terrestrial, vascular plants for mechanical support and in response to pathogen attack. Peroxidases have been proposed to catalyse the dehydrogenative polymerization of monolignols into lignins, although no specific isoenzyme has been shown...... to be involved in lignin biosynthesis. Recently we isolated an extracellular anionic peroxidase, ATP A2, from rapidly lignifying Arabidopsis cell suspension culture and cloned its cDNA. Here we show that the Atp A2 promoter directs GUS reporter gene expression in lignified tissues of transgenic plants. Moreover......-coumaryl and coniferyl alcohols are preferred by ATP A2, while the oxidation of sinapyl alcohol will be sterically hindered in ATP A2 as well as in all other plant peroxidases due to an overlap with the conserved Pro-139. We suggest ATP A2 is involved in a complex regulation of the covalent cross-linking in the plant...

  17. Substrate utilisation by plant-cell cultures

    Energy Technology Data Exchange (ETDEWEB)

    Fowler, M W

    1982-01-01

    Plant cell cultures have been grown on a wide range of carbon sources in addition to the traditional ones of sucrose and glucose. Biomass yields and growth rates vary greatly between the different carbon sources and there is a variation in response between different cell cultures to individual carbon sources. Some attempts have been made to grow cell cultures on 'waste' and related carbon sources, such as lactose, maltose, starch, molasses and milk whey. Only maltose was found to support growth to anything near the levels observed with glucose and sucrose. In the case of molasses carbon source cell growth was either non-existent or only just measurable. All the data point to glucose as being the most suitable carbon source, principally on the grounds of biomass yield and growth rate. It should be noted, however, that other carbon sources do appear to have a major (positive) influence on natural product synthesis. Uptake into the cell is an important aspect of carbohydrate utilisation. There is strong evidence that from disaccharides upwards, major degradation to smaller units occurs before uptake. In some cases the necessary enzymes appear to be excreted into the culture broth, in others they may be located within the cell wall; invertase that hydrolyses sucrose is a good example. Once the products of carbohydrate degradation and mobilisation enter the cell they may suffer one of two fates, oxidation or utilisation for biosynthesis. The precise split between these two varies depending on such factors as cell growth rate, cell size, nutrient broth composition and carbohydrate status of the cells. In general rapidly growing cells have a high rate of oxidation, whereas cells growing more slowly tend to be more directed towards biosynthesis. Carbohydrate utilisation is a key area of study, underpinning as it does both biomass yield and natural product synthesis. (Refs. 13).

  18. Plant cell technologies in space: Background, strategies and prospects

    Science.gov (United States)

    Kirkorian, A. D.; Scheld, H. W.

    1987-01-01

    An attempt is made to summarize work in plant cell technologies in space. The evolution of concepts and the general principles of plant tissue culture are discussed. The potential for production of high value secondary products by plant cells and differentiated tissue in automated, precisely controlled bioreactors is discussed. The general course of the development of the literature on plant tissue culture is highlighted.

  19. Plant cortical microtubule dynamics and cell division plane orientation

    NARCIS (Netherlands)

    Chakrabortty, Bandan

    2017-01-01

    This thesis work aimed at a better understanding of the molecular basis of oriented cell division in plant cell. As, the efficiency of plant morphogenesis depends on oriented cell division, this work should contribute towards a fundamental understanding of the molecular basis of efficient plant

  20. Plant Cell Adaptive Responses to Microgravity

    Science.gov (United States)

    Kordyum, Elizabeth; Kozeko, Liudmyla; Talalaev, Alexandr

    Microgravity is an abnormal environmental condition that plays no role in the functioning of biosphere. Nevertheless, the chronic effect of microgravity in space flight as an unfamiliar factor does not prevent the development of adaptive reactions at the cellular level. In real microgravity in space flight under the more or less optimal conditions for plant growing, namely temperature, humidity, CO2, light intensity and directivity in the hardware angiosperm plants perform an “reproductive imperative”, i.e. they flower, fruit and yield viable seeds. It is known that cells of a multicellular organism not only take part on reactions of the organism but also carry out processes that maintain their integrity. In light of these principles, the problem of the identification of biochemical, physiological and structural patterns that can have adaptive significance at the cellular and subcellular level in real and simulated microgravity is considered. Cytological studies of plants developing in real and simulated microgravity made it possible to establish that the processes of mitosis, cytokinesis, and tissue differentiation of vegetative and generative organs are largely normal. At the same time, under microgravity, essential reconstruction in the structural and functional organization of cell organelles and cytoskeleton, as well as changes in cell metabolism and homeostasis have been described. In addition, new interesting data concerning the influence of altered gravity on lipid peroxidation intensity, the level of reactive oxygen species, and antioxidant system activity, just like on the level of gene expression and synthesis of low-molecular and high-molecular heat shock proteins were recently obtained. So, altered gravity caused time-dependent increasing of the HSP70 and HSP90 levels in cells, that may indicate temporary strengthening of their functional loads that is necessary for re-establish a new cellular homeostasis. Relative qPCR results showed that

  1. 2003 Plant Cell Walls Gordon Conference

    Energy Technology Data Exchange (ETDEWEB)

    Daniel J. Cosgrove

    2004-09-21

    This conference will address recent progress in many aspects of cell wall biology. Molecular, genetic, and genomic approaches are yielding major advances in our understanding of the composition, synthesis, and architecture of plant cell walls and their dynamics during growth, and are identifying the genes that encode the machinery needed to make their biogenesis possible. This meeting will bring together international scientists from academia, industry and government labs to share the latest breakthroughs and perspectives on polysaccharide biosynthesis, wood formation, wall modification, expansion and interaction with other organisms, and genomic & evolutionary analyses of wall-related genes, as well as to discuss recent ''nanotechnological'' advances that take wall analysis to the level of a single cell.

  2. Vital Autofluorescence: Application to the Study of Plant Living Cells

    Directory of Open Access Journals (Sweden)

    Victoria V. Roshchina

    2012-01-01

    approach to study the autofluorescence of plant living cells—from cell diagnostics up to modelling the cell-cell contacts and cell interactions with fluorescent biologically active substances. It bases on the direct observations of secretions released from allelopathic and medicinal species and the cell-donor interactions with cell-acceptors as biosensors (unicellular plant generative and vegetative microspores. Special attention was paid to the interactions with pigmented and fluorescing components of the secretions released by the cells-donors from plant species. Colored components of secretions are considered as histochemical dyes for the analysis of cellular mechanisms at the cell-cell contacts and modelling of cell-cell interactions. The fluorescence of plant biosensors was also recommended for the testing of natural plant excretions as medical drugs.

  3. Plant and animal stem cells: similar yet different

    NARCIS (Netherlands)

    Heidstra, R.; Sabatini, S.

    2014-01-01

    The astonishingly long lives of plants and their regeneration capacity depend on the activity of plant stem cells. As in animals, stem cells reside in stem cell niches, which produce signals that regulate the balance between self-renewal and the generation of daughter cells that differentiate into

  4. Molecular regulation of plant cell wall extensibility

    Science.gov (United States)

    Cosgrove, D. J.

    1998-01-01

    Gravity responses in plants often involve spatial and temporal changes in cell growth, which is regulated primarily by controlling the ability of the cell wall to extend. The wall is thought to be a cellulose-hemicellulose network embedded in a hydrated matrix of complex polysaccharides and a small amount of structural protein. The wall extends by a form of polymer creep, which is mediated by expansins, a novel group of wall-loosening proteins. Expansins were discovered during a molecular dissection of the "acid growth" behavior of cell walls. Expansin alters the rheology of plant walls in profound ways, yet its molecular mechanism of action is still uncertain. It lacks detectable hydrolytic activity against the major components of the wall, but it is able to disrupt noncovalent adhesion between wall polysaccharides. The discovery of a second family of expansins (beta-expansins) sheds light on the biological role of a major group of pollen allergens and implies that expansins have evolved for diverse developmental functions. Finally, the contribution of other processes to wall extensibility is briefly summarized.

  5. PHYTOCHEMICAL STUDY OF CELL CULTURE JATROPHA CURCAS

    Directory of Open Access Journals (Sweden)

    KOMAR RUSLAN

    2011-01-01

    Full Text Available Jatropha curcas belongs to the Euphorbiaceae family which has potential economically. This plant has been reported to contain toxic compounds such as curcin and phorbol ester and its derivatives. These compounds may become a problem if J. curcas will be explored as a source of biofuel. In order to provide safety plants, the research on the study of phytochemical and initiation of cell and organ culture have been carried out. J curcas which has been collected from different regions in Indonesia showed to contain relatively the same profile of chemical contents. Dominant compounds that were detected by GCMS are hidrocarbon such as 2-heptenal, decadienal, hexsadecane, pentadecane, cyclooctane etc, fatty acid such as oktadecanoate acid, etthyl linoleate, ethyl stearate, heksadecanoate acid and steroid such as stigmasterol, fucosterol, sitosterol. No phorbol ester and its derivatives have been detected yet by the GCMS method. Callus and suspension cultures of J. curcas have been established to be used for further investigation.

  6. Morphological, biochemical and genetic influence of mutagen treatments on medicinal plant tissue cultures

    International Nuclear Information System (INIS)

    Onisei, T.; Toth, E.; Tesio, B.; Floria, F.

    1994-01-01

    Gamma rays and/or alkylant agents have been applied on callus tissue, young regenerants and cell suspension in order to establish their effect on morphogenesis, regeneration ability and biosynthetic potential. Growth dynamics, morpho-anatomic variables, secondary metabolite production, cell cytogenetics, enzyme specific activities, isoperoxidase and isoesterase patterns were analyzed in relation to the morphogenetic response of Atropa belladonna, Datura innoxia, Lavandula angustifolia, Chamomilla recutita, Digitalis lanata and Vinca minor tissue cultures. The effects of gamma-ray doses varied from one species to another; 10 to 20 Gy were generally able to stimulate growth and plant regeneration (via organogenesis and somatic embryogenesis), while 10 to 50 Gy enhanced secondary metabolite biosynthesis both in callus and cell suspension culture. Semnificative increase of secondary metabolite production was obtained when treatments with EMS (0.1-0.2%) have been applied to young regenerants. Many differences in biological features and biochemical behaviour were registered 20 days and one year, respectively, after treatment. (author)

  7. Somatic embryogenesis in cell cultures of Glycine species.

    Science.gov (United States)

    Gamborg, O L; Davis, B P; Stahlhut, R W

    1983-08-01

    This report describes the development of procedures for the production of somatic embryos in cell cultures of Glycine species including soybean. The conditions for callus induction and initiation of rapidly growing cell suspension cultures were defined. Methods for inducing embryogenesis were tested on 16 lines of several Glycine species and cultivars of soybean. The SB-26 Culture of a G. soja gave the best results and was used in the experiments. Embryogenesis required the presence of picloram or 2,4-D. AMO 1618, CCC, PP-333 and Ancymidol enhanced the embryogenesis frequency. Plants of the G. soja (SB-26) were grown to maturity from seed-derived shoot tips. Characteristics of the plants are discussed.

  8. Dynamic simulation of a direct carbonate fuel cell power plant

    Energy Technology Data Exchange (ETDEWEB)

    Ernest, J.B. [Fluor Daniel, Inc., Irvine, CA (United States); Ghezel-Ayagh, H.; Kush, A.K. [Fuel Cell Engineering, Danbury, CT (United States)

    1996-12-31

    Fuel Cell Engineering Corporation (FCE) is commercializing a 2.85 MW Direct carbonate Fuel Cell (DFC) power plant. The commercialization sequence has already progressed through construction and operation of the first commercial-scale DFC power plant on a U.S. electric utility, the 2 MW Santa Clara Demonstration Project (SCDP), and the completion of the early phases of a Commercial Plant design. A 400 kW fuel cell stack Test Facility is being built at Energy Research Corporation (ERC), FCE`s parent company, which will be capable of testing commercial-sized fuel cell stacks in an integrated plant configuration. Fluor Daniel, Inc. provided engineering, procurement, and construction services for SCDP and has jointly developed the Commercial Plant design with FCE, focusing on the balance-of-plant (BOP) equipment outside of the fuel cell modules. This paper provides a brief orientation to the dynamic simulation of a fuel cell power plant and the benefits offered.

  9. Roles of membrane trafficking in plant cell wall dynamics

    Directory of Open Access Journals (Sweden)

    Kazuo eEbine

    2015-10-01

    Full Text Available The cell wall is one of the characteristic components of plant cells. The cell wall composition differs among cell types and is modified in response to various environmental conditions. To properly generate and modify the cell wall, many proteins are transported to the plasma membrane or extracellular space through membrane trafficking, which is one of the key protein transport mechanisms in eukaryotic cells. Given the diverse composition and functions of the cell wall in plants, the transport of the cell wall components and proteins that are involved in cell wall-related events could be specialized for each cell type, i.e., the machinery for cell wall biogenesis, modification, and maintenance could be transported via different trafficking pathways. In this review, we summarize the recent progress in the current understanding of the roles and mechanisms of membrane trafficking in plant cells and focus on the biogenesis and regulation of the cell wall.

  10. Effects of aluminum on growth, polyamine metabolism, and inorganic ions in suspension cultures of red spruce (Picea rubens)

    Science.gov (United States)

    Rakesh Minocha; Walter C. Shortle; Daniel J. Jr. Coughin; Subhash C. Minocha

    1996-01-01

    The influence of age of red spruce (Picea rubens Sarg.) cell suspensions on aluminum (Al) effects was studied by adding AICI3 (0.2, 0.5, and 1.0 mM) to the media on each day of a 7-day culture period and analyzing for changes in total cell mass, polyamines, arginine decarboxylase activity, and inorganic ions after 24 h of...

  11. Screening and selection of high carotenoid producing in vitro tomato cell culture lines for [13C]-carotenoid production.

    Science.gov (United States)

    Engelmann, Nancy J; Campbell, Jessica K; Rogers, Randy B; Rupassara, S Indumathie; Garlick, Peter J; Lila, Mary Ann; Erdman, John W

    2010-09-22

    Isotopically labeled tomato carotenoids, phytoene, phytofluene, and lycopene, are needed for mammalian bioavailability and metabolism research but are currently commercially unavailable. The goals of this work were to establish and screen multiple in vitro tomato cell lines for carotenoid production, test the best producers with or without the bleaching herbicides, norflurazon and 2-(4-chlorophenyl-thio)triethylamine (CPTA), and to use the greatest carotenoid accumulator for in vitro 13C-labeling. Different Solanum lycopersicum allelic variants for high lycopene and varying herbicide treatments were compared for carotenoid accumulation in callus and suspension culture, and cell suspension cultures of the hp-1 line were chosen for isotopic labeling. When grown with [U]-13C-glucose and treated with CPTA, hp-1 suspensions yielded highly enriched 13C-lycopene with 45% of lycopene in the M+40 form and 88% in the M+35 to M+40 isotopomer range. To the authors' knowledge this is the first report of highly enriched 13C-carotenoid production from in vitro plant cell culture.

  12. Outside-in control -Does plant cell wall integrity regulate cell cycle progression?

    Science.gov (United States)

    Gigli-Bisceglia, Nora; Hamann, Thorsten

    2018-04-13

    During recent years it has become accepted that plant cell walls are not inert objects surrounding all plant cells but are instead highly dynamic, plastic structures. They are involved in a large number of cell biological processes and contribute actively to plant growth, development and interaction with environment. Therefore, it is not surprising that cellular processes can control plant cell wall integrity while, simultaneously, cell wall integrity can influence cellular processes. In yeast and animal cells such a bi-directional relationship also exists between the yeast/animal extra-cellular matrices and the cell cycle. In yeast, the cell wall integrity maintenance mechanism and a dedicated plasmamembrane integrity checkpoint are mediating this relationship. Recent research has yielded insights into the mechanism controlling plant cell wall metabolism during cytokinesis. However, knowledge regarding putative regulatory pathways controlling adaptive modifications in plant cell cycle activity in response to changes in the state of the plant cell wall are not yet identified. In this review, we summarize similarities and differences in regulatory mechanisms coordinating extra cellular matrices and cell cycle activity in animal and yeast cells, discuss the available evidence supporting the existence of such a mechanism in plants and suggest that the plant cell wall integrity maintenance mechanism might also control cell cycle activity in plant cells. This article is protected by copyright. All rights reserved.

  13. An oil-soluble extract of Rubus idaeus cells enhances hydration and water homeostasis in skin cells.

    Science.gov (United States)

    Tito, A; Bimonte, M; Carola, A; De Lucia, A; Barbulova, A; Tortora, A; Colucci, G; Apone, F

    2015-12-01

    Raspberry plants, belonging to the species of Rubus idaeus, are known for their excellent therapeutic properties as they are particularly rich in compounds with strong antioxidant activity, which promote health and well-being of human cells. Besides their high content of phenolic compounds, Rubus plants are rich in oil-soluble compounds, which are also primary components of the hydrolipidic film barrier of the skin. As plant cell cultures represented a valuable system to produce interesting compounds and ingredients for cosmetic applications, we developed liquid suspension cultures from Rubus idaeus leaves and used them to obtain an active ingredient aimed at improving hydration and moisturization capacity in the skin. Rubus idaeus cells, grown in the laboratory under sterile and controlled conditions as liquid suspension cultures, were processed to obtain an oil-soluble (liposoluble) extract, containing phenolic compounds and a wide range of fatty acids. The extract was tested on cultured keratinocytes and fibroblasts and then on the skin in vivo, to assess its cosmetic activities. When tested on skin cell cultures, the extract induced the genes responsible for skin hydration, such as aquaporin 3, filaggrin, involucrin and hyaluronic acid synthase, and stimulated the expression and the activity of the enzyme glucocerebrosidase, involved in ceramide production. Moreover, the liposoluble extract increased the synthesis of the extracellular matrix components in cultured fibroblasts and showed a remarkable skin-hydrating capacity when tested on human skin in vivo. Thanks to these activities, the Rubus idaeus liposoluble extract has several potential applications in skin care cosmetics: it can be used as hydrating and moisturizing ingredient in face and body lotions, and as anti-ageing product in face creams specifically designed to fight wrinkle formation. © 2015 Society of Cosmetic Scientists and the Société Française de Cosmétologie.

  14. Agrobacterium -induced hypersensitive necrotic reaction in plant cells

    African Journals Online (AJOL)

    High necrosis and poor survival rate of target plant tissues are some of the major factors that affect the efficiency of Agrobacterium-mediated T-DNA transfer into plant cells. These factors may be the result of, or linked to, hypersensitive defense reaction in plants to Agrobacterium infection, which may involve the recognition ...

  15. Proteomic characterization of golgi membranes enriched from Arabidopsis suspension cell cultures

    DEFF Research Database (Denmark)

    Hansen, Sara Fasmer; Ebert, Berit; Rautengarten, Carsten

    2016-01-01

    The plant Golgi apparatus has a central role in the secretory pathway and is the principal site within the cell for the assembly and processing of macromolecules. The stacked membrane structure of the Golgi apparatus along with its interactions with the cytoskeleton and endoplasmic reticulum has...... historically made the isolation and purification of this organelle difficult. Density centrifugation has typically been used to enrich Golgi membranes from plant microsomal preparations, and aside from minor adaptations, the approach is still widely employed. Here we outline the enrichment of Golgi membranes...... from an Arabidopsis cell suspension culture that can be used to investigate the proteome of this organelle. We also provide a useful workflow for the examination of proteomic data as the result of multiple analyses. Finally, we highlight a simple technique to validate the subcellular localization...

  16. Inhibition of protease activity by antisense RNA improves recombinant protein production in Nicotiana tabacum cv. Bright Yellow 2 (BY-2) suspension cells.

    Science.gov (United States)

    Mandal, Manoj K; Fischer, Rainer; Schillberg, Stefan; Schiermeyer, Andreas

    2014-08-01

    Recombinant proteins produced in plant suspension cultures are often degraded by endogenous plant proteases when secreted into the medium, resulting in low yields. To generate protease-deficient tobacco BY-2 cell lines and to retrieve the sequence information, we cloned four different protease cDNAs from tobacco BY-2 cells (NtAP, NtCP, NtMMP1, and NtSP), which represent the major catalytic classes. The simultaneous expression of antisense RNAs against these endogenous proteases led to the establishment of cell lines with reduced levels of endogenous protease expression and activity at late stages of the cultivation cycle. One of the cell lines showing reduced proteolytic activity in the culture medium was selected for the expression of the recombinant full-length IgG1(κ) antibody 2F5, recognizing the gp41 surface protein of HIV-1. This cell line showed significantly reduced degradation of the 2F5 heavy chain, resulting in four-fold higher accumulation of the intact antibody heavy chain when compared to transformed wild type cells expressing the same antibody. N-terminal sequencing data revealed that the antibody has two cleavage sites within the CDR-H3 and one site at the end of the H4-framework region. These cleavage sites are found to be vulnerable to serine proteases. The data provide a basis for further improvement of plant cells for the production of recombinant proteins in plant cell suspension cultures. Copyright © 2014 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  17. Progress and prospects for phosphoric acid fuel cell power plants

    Energy Technology Data Exchange (ETDEWEB)

    Bonville, L.J.; Scheffler, G.W.; Smith, M.J. [International Fuel Cells Corp., South Windsor, CT (United States)

    1996-12-31

    International Fuel Cells (IFC) has developed the fuel cell power plant as a new, on-site power generation source. IFC`s commercial fuel cell product is the 200-kW PC25{trademark} power plant. To date over 100 PC25 units have been manufactured. Fleet operating time is in excess of one million hours. Individual units of the initial power plant model, the PC25 A, have operated for more than 30,000 hours. The first model {open_quotes}C{close_quotes} power plant has over 10,000 hours of operation. The manufacturing, application and operation of this power plant fleet has established a firm base for design and technology development in terms of a clear understanding of the requirements for power plant reliability and durability. This fleet provides the benchmark against which power plant improvements must be measured.

  18. Plant Systems Biology at the Single-Cell Level.

    Science.gov (United States)

    Libault, Marc; Pingault, Lise; Zogli, Prince; Schiefelbein, John

    2017-11-01

    Our understanding of plant biology is increasingly being built upon studies using 'omics and system biology approaches performed at the level of the entire plant, organ, or tissue. Although these approaches open new avenues to better understand plant biology, they suffer from the cellular complexity of the analyzed sample. Recent methodological advances now allow plant scientists to overcome this limitation and enable biological analyses of single-cells or single-cell-types. Coupled with the development of bioinformatics and functional genomics resources, these studies provide opportunities for high-resolution systems analyses of plant phenomena. In this review, we describe the recent advances, current challenges, and future directions in exploring the biology of single-cells and single-cell-types to enhance our understanding of plant biology as a system. Copyright © 2017 Elsevier Ltd. All rights reserved.

  19. The study of accumulation of Sr 90 by plant cells

    International Nuclear Information System (INIS)

    Matusov, G.D.; Kudryashova, N.N.

    2002-01-01

    In this work the absorption and desorption of ions Sr 90 by plant cells and influence of different physical and chemical factors of environment on that processes were investigated. The kinetics of strontium accumulation have been obtained and the factors of accumulation of Sr 90 have been determined for a plant cell itself and its separate compartments

  20. A dynamical model for plant cell wall architecture formation.

    NARCIS (Netherlands)

    Mulder, B.M.; Emons, A.M.C.

    2001-01-01

    We discuss a dynamical mathematical model to explain cell wall architecture in plant cells. The highly regular textures observed in cell walls reflect the spatial organisation of the cellulose microfibrils (CMFs), the most important structural component of cell walls. Based on a geometrical theory

  1. Plant programmed cell death, ethylene and flower senescence

    NARCIS (Netherlands)

    Woltering, E.J.; Jong, de A.; Hoeberichts, F.A.; Iakimova, E.T.; Kapchina, V.

    2005-01-01

    Programmed cell death (PCD) applies to cell death that is part of the normal life of multicellular organisms. PCD is found throughout the animal and plant kingdoms; it is an active process in which a cell suicide pathway is activated resulting in controlled disassembly of the cell. Most cases of PCD

  2. Animal and plant stem cells concepts, propagation and engineering

    CERN Document Server

    Pavlović, Mirjana

    2017-01-01

    This book provides a multifaceted look into the world of stem cells and explains the similarities and differences between plant and human stem cells. It explores the intersection between animals and plants and explains their cooperative role in bioengineering studies. The book treats both theoretical and practical aspects of stem cell research. It covers the advantages and limitations of many common applications related to stem cells: their sources, categories, engineering of these cells, reprogramming of their functions, and their role as novel cellular therapeutic approach. Written by experts in the field, the book focuses on aspects of stem cells ranging from expansion-propagation to metabolic reprogramming. It introduces the emergence of cancer stem cells and different modalities in targeted cancer stem cell therapies. It is a valuable source of fresh information for academics and researchers, examining molecular mechanisms of animal and plant stem cell regulation and their usage for therapeutic applicati...

  3. Role of cellular antioxidants (glutathione and ascorbic acid) in the growth and development of wild carrot suspension cultures

    International Nuclear Information System (INIS)

    Earnshaw, B.A.

    1986-01-01

    Determinations of endogenous glutathione (GSH), glutathione disulfide (GSSG), ascorbic acid (AA) and dehydroascorbic acid (DHA) in proliferating and developing wild carrot cultures showed that lower levels of GSH and AA were associated with developing cultures. The GSSG and DHA levels did not account for the changes in the levels of antioxidants between proliferating and developing cultures. Studies were designed to test an observed auxin (2,4-Dichlorophenoxyacetic acid, 2,4-D)-antioxidant association. Two fractions (embryo and less developed) were obtained by screening developed cultures which were previously grown in the presence of 14 C-2, 4-D. The embryo fraction had a lower concentration of 14 C than the less developed fraction, supporting the association, since the two fractions showed this relationship with respect to GSH and AA concentrations. Determinations of GSH and AA levels of cells grown in various concentrations of 2,4-D showed the association, decreases in the 2,4-D concentration correlated with decreases in the GSH and AA concentrations. The existence of a respiratory pathway involving GSSG reductase, DHA reductase, and AA oxidase was investigated to test whether inhibition of AA oxidase by 2,4-D could explain the auxin-antioxidant association; however, AA oxidase activity was not detected

  4. Penium margaritaceum as a model organism for cell wall analysis of expanding plant cells.

    Science.gov (United States)

    Rydahl, Maja G; Fangel, Jonatan U; Mikkelsen, Maria Dalgaard; Johansen, I Elisabeth; Andreas, Amanda; Harholt, Jesper; Ulvskov, Peter; Jørgensen, Bodil; Domozych, David S; Willats, William G T

    2015-01-01

    The growth of a plant cell encompasses a complex set of subcellular components interacting in a highly coordinated fashion. Ultimately, these activities create specific cell wall structural domains that regulate the prime force of expansion, internally generated turgor pressure. The precise organization of the polymeric networks of the cell wall around the protoplast also contributes to the direction of growth, the shape of the cell, and the proper positioning of the cell in a tissue. In essence, plant cell expansion represents the foundation of development. Most studies of plant cell expansion have focused primarily upon late divergent multicellular land plants and specialized cell types (e.g., pollen tubes, root hairs). Here, we describe a unicellular green alga, Penium margaritaceum (Penium), which can serve as a valuable model organism for understanding cell expansion and the underlying mechanics of the cell wall in a single plant cell.

  5. Characterization of a cartilage-like engineered biomass using a self-aggregating suspension culture model: molecular composition using FT-IRIS.

    Science.gov (United States)

    Kim, Minwook; Kraft, Jeffrey J; Volk, Andrew C; Pugarelli, Joan; Pleshko, Nancy; Dodge, George R

    2011-12-01

    Maintenance of chondrocyte phenotype and robust expression and organization of macromolecular components with suitable cartilaginous properties is an ultimate goal in cartilage tissue engineering. We used a self-aggregating suspension culture (SASC) method to produce an engineered cartilage, "cartilage tissue analog" (CTA). With an objective of understanding the stability of phenotype of the CTA over long periods, we cultured chondrocytes up to 4 years and analyzed the matrix. Both early (eCTAs) (6 months) and aged (aCTAs) (4 years) showed type II collagen throughout with higher concentrations near the edge. Using Fourier transform-infrared imaging spectroscopy (FT-IRIS), proteoglycan/collagen ratio of eCTA was 2.8 times greater than native cartilage at 1 week, but the ratio was balanced to native level (p = 0.017) by 36 weeks. Surprisingly, aCTAs maintained the hyaline characteristics, but there was evidence of calcification within the tissue with a distinct range of intensities. Mineral/matrix ratio of those aCTA with "intensive" calcification was significantly higher (p = 0.017) than the "partial," but when compared to native bone the ratio of "intensive" aCTAs was 2.4 times lower. In this study we utilized the imaging approach of FT-IRIS and have shown that a biomaterial formed is compositionally closely related to natural cartilage for long periods in culture. We show that this culture platform can maintain a CTA for extended periods of time (4 years) and under those conditions signs of mineralization can be found. This method of cartilage tissue engineering is a promising method to generate cartilaginous biomaterial and may have potential to be utilized in both cartilage and boney repairs. Copyright © 2011 Orthopaedic Research Society.

  6. Calculation of absorbed dose of anchorage-dependent cells from internal beta-rays irradiation

    International Nuclear Information System (INIS)

    Chen Jianwei; Huang Gang; Li Shijun

    2001-01-01

    Objective: To elicit the formula of internal dosimetry in anchorage-dependent cells by beta-emitting radionuclides from uniformly distributed volume sources. Methods: By means of the definition of absorbed dose and the MIRD (Medical International Radiation Dose) scheme the formula of internal dosimetry was reasonably deduced. Firstly, studying the systems of suspension culture cells. Then, taking account of the speciality of the systems of the anchorage-dependent cells and the directions of irradiation, the absorbed dose of anchorage -dependent cells was calculated by the accumulated radioactivity, beta-ray energy, and the volume of the cultured systems. Results: The formula of internal dosimetry of suspension culture cells and anchorage-dependent cells were achieved. At the same time, the formula of internal dosimetry of suspension culture cells was compared with that of MIRD and was confirmed accurate. Conclusion: The formula of internal dosimetry is concise, reliable and accurate

  7. Lethal impacts of cigarette smoke in cultured tobacco cells

    Directory of Open Access Journals (Sweden)

    Kawano Tomonori

    2011-07-01

    Full Text Available Abstract Background In order to understand and generalize the toxic mechanism of cigarette smoke in living cells, comparison of the data between animal systems and other biological system such as microbial and plant systems is highly beneficial. Objective By employing the tobacco cells as model materials for cigarette smoke toxicity assay, the impacts of the combustion by-products such as nitrogen oxides could be highlighted as the toxic impacts of the plant-derived endogenous chemicals could be excluded in the plant cells. Methods Cigarette smoke-induced cell death was assessed in tobacco cell suspension cultures in the presence and absence of pharmacological inhibitors. Results Cigarette smoke was effective in induction of cell death. The smoke-induced cell death could be partially prevented by addition of nitric oxide (NO scavenger, suggesting the role for NO as the cell death mediator. Addition of NO donor to tobacco cells also resulted in development of partial cell death further confirming the role of NO as cell death mediator. Members of reactive oxygen species and calcium ion were shown to be protecting the cells from the toxic action of smoke-derived NO.

  8. Measuring the elasticity of plant cells with atomic force microscopy.

    Science.gov (United States)

    Braybrook, Siobhan A

    2015-01-01

    The physical properties of biological materials impact their functions. This is most evident in plants where the cell wall contains each cell's contents and connects each cell to its neighbors irreversibly. Examining the physical properties of the plant cell wall is key to understanding how plant cells, tissues, and organs grow and gain the shapes important for their respective functions. Here, we present an atomic force microscopy-based nanoindentation method for examining the elasticity of plant cells at the subcellular, cellular, and tissue level. We describe the important areas of experimental design to be considered when planning and executing these types of experiments and provide example data as illustration. Copyright © 2015 Elsevier Inc. All rights reserved.

  9. Involvement of ethylene and lipid signalling in cadmium-induced programmed cell death in tomato suspension cells

    NARCIS (Netherlands)

    Yakimova, E.T.; Kapchina-Toteva, V.M.; Laarhoven, L.J.J.; Harren, F.J.M.; Woltering, E.J.

    2006-01-01

    Cadmium-induced cell death was studied in suspension-cultured tomato (Lycopersicon esculentum Mill.) cells (line MsK8) treated with CdSO4. Within 24 h, cadmium treatment induced cell death in a concentration-dependent manner. Cell cultures showed recovery after 23 days which indicates the existence

  10. Involvement of ethylene and lipid signalling in cadmium-induced programmed cell death in tomato suspension cells

    NARCIS (Netherlands)

    Iakimova, E.T.; Kapchina-Toteva, V.M.; Laarhoven, L.J.; Harren, F.; Woltering, E.J.

    2006-01-01

    Cadmium-induced cell death was studied in suspension-cultured tomato (Lycopersicon esculentum Mill.) cells (line MsK8) treated with CdSO4. Within 24 h, cadmium treatment induced cell death in a concentration-dependent manner. Cell cultures showed recovery after 2¿3 days which indicates the existence

  11. Super-resolution Microscopy in Plant Cell Imaging.

    Science.gov (United States)

    Komis, George; Šamajová, Olga; Ovečka, Miroslav; Šamaj, Jozef

    2015-12-01

    Although the development of super-resolution microscopy methods dates back to 1994, relevant applications in plant cell imaging only started to emerge in 2010. Since then, the principal super-resolution methods, including structured-illumination microscopy (SIM), photoactivation localization microscopy (PALM), stochastic optical reconstruction microscopy (STORM), and stimulated emission depletion microscopy (STED), have been implemented in plant cell research. However, progress has been limited due to the challenging properties of plant material. Here we summarize the basic principles of existing super-resolution methods and provide examples of applications in plant science. The limitations imposed by the nature of plant material are reviewed and the potential for future applications in plant cell imaging is highlighted. Copyright © 2015 Elsevier Ltd. All rights reserved.

  12. Plant cell tissue culture: A potential source of chemicals

    Energy Technology Data Exchange (ETDEWEB)

    Scott, C.D.; Dougall, D.K.

    1987-08-01

    Higher plants produce many industrially important products. Among these are drugs and medicinal chemicals, essential oils and flavors, vegetable oils and fats, fine and specialty chemicals, and even some commodity chemicals. Although, currently, whole-plant extraction is the primary means of harvesting these materials, the advent of plant cell tissue culture could be a much more effective method of producing many types of phytochemicals. The use of immobilized plant cells in an advanced bioreactor configuration with excretion of the product into the reactor medium may represent the most straightforward way of commercializing such techniques for lower-value chemicals. Important research and development opportunities in this area include screening for plant cultures for nonmedical, lower-value chemicals; understanding and controlling plant cell physiology and biochemistry; optimizing effective immobilization methods; developing more efficient bioreactor concepts; and perfecting product extraction and purification techniques. 62 refs., 2 figs.

  13. Gateway binary vectors with the bialaphos resistance gene, bar, as a selection marker for plant transformation.

    Science.gov (United States)

    Nakamura, Shinya; Mano, Shoji; Tanaka, Yuji; Ohnishi, Masato; Nakamori, Chihiro; Araki, Masami; Niwa, Tomoko; Nishimura, Mikio; Kaminaka, Hironori; Nakagawa, Tsuyoshi; Sato, Yutaka; Ishiguro, Sumie

    2010-01-01

    We constructed two series of Gateway binary vectors, pGWBs and R4pGWBs, possessing the bialaphos resistance gene (bar) as a selection marker for plant transformation. The reporters and tags employed in this system are sGFP, GUS, LUC, EYFP, ECFP, G3GFP, mRFP, TagRFP, 6xHis, FLAG, 3xHA, 4xMyc, 10xMyc, GST, T7 and TAP. Selection of Arabidopsis transformants with BASTA was successfully carried out using both plate-grown and soil-grown seedlings. Transformed rice calli and suspension-cultured tobacco cells were selected on plates containing BASTA or glufosinate-ammonium. These vectors are compatible with existing pGWB and R4pGWB vectors carrying kanamycin and hygromycin B resistance.

  14. PECULIARITIES OF SECONDARY METABOLITES BIOSYNTHESIS IN PLANT CELL CULTURES

    Directory of Open Access Journals (Sweden)

    A.M. NOSOV

    2014-06-01

    Full Text Available metabolites formation in plant cell cultures of Panax spp., (ginsenosides; Dioscorea deltoidea (steroid glycosides; Ajuga reptans, Serratula coronata, Rhaponticum carthamoides (ecdisteroids; Polyscias spp., (triterpene glycosides, Taxus spp. (taxoids, Stevia rebaudiana (diterpene steviol-glycosides, Stephania glabra (alkaloids. They are some regular trends of secondary metabolites synthesis in the plant cell culture:It can be noted the stable synthesis of the compound promoting cell proliferation. Indeed, cell cultures of Dioscorea deltoidea were demonstrated to accumulate only furostanol glycosides, which promoted cell division. Furostanol glycoside content of Dioscorea strain DM-0.5 was up to 6 - 12% by dry biomass.Panax ginseng and P. japonicus plant cell cultures synthesize as minimum seven triterpene glycosides (ginsenosides, the productivity of these compounds was up to 6.0 - 8.0% on dry biomass.By contrast, the detectable synthesis of diterpene steviol-glycosides in cultivated cells of Stevia rebaudiana initiated in the mixotrophic cultures during chloroplast formation only.Despite these differences, or mainly due to them, plant cell cultures have become an attractive source of phytochemicals in alternative to collecting wild plants. It provides a guideline to bioreactor-based production of isoprenoids using undifferentiated plant cell cultures. 

  15. Incorporation of mammalian actin into microfilaments in plant cell nucleus

    Directory of Open Access Journals (Sweden)

    Paves Heiti

    2004-04-01

    Full Text Available Abstract Background Actin is an ancient molecule that shows more than 90% amino acid homology between mammalian and plant actins. The regions of the actin molecule that are involved in F-actin assembly are largely conserved, and it is likely that mammalian actin is able to incorporate into microfilaments in plant cells but there is no experimental evidence until now. Results Visualization of microfilaments in onion bulb scale epidermis cells by different techniques revealed that rhodamine-phalloidin stained F-actin besides cytoplasm also in the nuclei whereas GFP-mouse talin hybrid protein did not enter the nuclei. Microinjection of fluorescently labeled actin was applied to study the presence of nuclear microfilaments in plant cells. Ratio imaging of injected fluorescent rabbit skeletal muscle actin and phalloidin staining of the microinjected cells showed that mammalian actin was able to incorporate into plant F-actin. The incorporation occurred preferentially in the nucleus and in the perinuclear region of plant cells whereas part of plant microfilaments, mostly in the periphery of cytoplasm, did not incorporate mammalian actin. Conclusions Microinjected mammalian actin is able to enter plant cell's nucleus, whereas incorporation of mammalian actin into plant F-actin occurs preferentially in the nucleus and perinuclear area.

  16. Small molecule probes for plant cell wall polysaccharide imaging

    Directory of Open Access Journals (Sweden)

    Ian eWallace

    2012-05-01

    Full Text Available Plant cell walls are composed of interlinked polymer networks consisting of cellulose, hemicelluloses, pectins, proteins, and lignin. The ordered deposition of these components is a dynamic process that critically affects the development and differentiation of plant cells. However, our understanding of cell wall synthesis and remodeling, as well as the diverse cell wall architectures that result from these processes, has been limited by a lack of suitable chemical probes that are compatible with live-cell imaging. In this review, we summarize the currently available molecular toolbox of probes for cell wall polysaccharide imaging in plants, with particular emphasis on recent advances in small molecule-based fluorescent probes. We also discuss the potential for further development of small molecule probes for the analysis of cell wall architecture and dynamics.

  17. Why plants make puzzle cells, and how their shape emerges.

    Science.gov (United States)

    Sapala, Aleksandra; Runions, Adam; Routier-Kierzkowska, Anne-Lise; Das Gupta, Mainak; Hong, Lilan; Hofhuis, Hugo; Verger, Stéphane; Mosca, Gabriella; Li, Chun-Biu; Hay, Angela; Hamant, Olivier; Roeder, Adrienne Hk; Tsiantis, Miltos; Prusinkiewicz, Przemyslaw; Smith, Richard S

    2018-02-27

    The shape and function of plant cells are often highly interdependent. The puzzle-shaped cells that appear in the epidermis of many plants are a striking example of a complex cell shape, however their functional benefit has remained elusive. We propose that these intricate forms provide an effective strategy to reduce mechanical stress in the cell wall of the epidermis. When tissue-level growth is isotropic, we hypothesize that lobes emerge at the cellular level to prevent formation of large isodiametric cells that would bulge under the stress produced by turgor pressure. Data from various plant organs and species support the relationship between lobes and growth isotropy, which we test with mutants where growth direction is perturbed. Using simulation models we show that a mechanism actively regulating cellular stress plausibly reproduces the development of epidermal cell shape. Together, our results suggest that mechanical stress is a key driver of cell-shape morphogenesis. © 2018, Sapala et al.

  18. Vacuolar processing enzyme: an executor of plant cell death.

    Science.gov (United States)

    Hara-Nishimura, Ikuko; Hatsugai, Noriyuki; Nakaune, Satoru; Kuroyanagi, Miwa; Nishimura, Mikio

    2005-08-01

    Apoptotic cell death in animals is regulated by cysteine proteinases called caspases. Recently, vacuolar processing enzyme (VPE) was identified as a plant caspase. VPE deficiency prevents cell death during hypersensitive response and cell death of limited cell layers at the early stage of embryogenesis. Because plants do not have macrophages, dying cells must degrade their materials by themselves. VPE plays an essential role in the regulation of the lytic system of plants during the processes of defense and development. VPE is localized in the vacuoles, unlike animal caspases, which are localized in the cytosol. Thus, plants might have evolved a regulated cellular suicide strategy that, unlike animal apoptosis, is mediated by VPE and the vacuoles.

  19. Plant natriuretic peptides induce proteins diagnostic for an adaptive response to stress

    KAUST Repository

    Turek, Ilona; Marondedze, Claudius; Wheeler, Janet I.; Gehring, Christoph A; Irving, Helen R.

    2014-01-01

    In plants, structural and physiological evidence has suggested the presence of biologically active natriuretic peptides (PNPs). PNPs are secreted into the apoplast, are systemically mobile and elicit a range of responses signaling via cGMP. The PNP-dependent responses include tissue specific modifications of cation transport and changes in stomatal conductance and the photosynthetic rate. PNP also has a critical role in host defense responses. Surprisingly, PNP-homologs are produced by several plant pathogens during host colonization suppressing host defense responses. Here we show that a synthetic peptide representing the biologically active fragment of the Arabidopsis thaliana PNP (AtPNP-A) induces the production of reactive oxygen species in suspension-cultured A. thaliana (Col-0) cells. To identify proteins whose expression changes in an AtPNP-A dependent manner, we undertook a quantitative proteomic approach, employing tandem mass tag (TMT) labeling, to reveal temporal responses of suspension-cultured cells to 1 nM and 10 pM PNP at two different time-points post-treatment. Both concentrations yield a distinct differential proteome signature. Since only the higher (1 nM) concentration induces a ROS response, we conclude that the proteome response at the lower concentration reflects a ROS independent response. Furthermore, treatment with 1 nM PNP results in an over-representation of the gene ontology (GO) terms “oxidation-reduction process,” “translation” and “response to salt stress” and this is consistent with a role of AtPNP-A in the adaptation to environmental stress conditions.

  20. Plant natriuretic peptides induce proteins diagnostic for an adaptive response to stress

    KAUST Repository

    Turek, Ilona

    2014-11-26

    In plants, structural and physiological evidence has suggested the presence of biologically active natriuretic peptides (PNPs). PNPs are secreted into the apoplast, are systemically mobile and elicit a range of responses signaling via cGMP. The PNP-dependent responses include tissue specific modifications of cation transport and changes in stomatal conductance and the photosynthetic rate. PNP also has a critical role in host defense responses. Surprisingly, PNP-homologs are produced by several plant pathogens during host colonization suppressing host defense responses. Here we show that a synthetic peptide representing the biologically active fragment of the Arabidopsis thaliana PNP (AtPNP-A) induces the production of reactive oxygen species in suspension-cultured A. thaliana (Col-0) cells. To identify proteins whose expression changes in an AtPNP-A dependent manner, we undertook a quantitative proteomic approach, employing tandem mass tag (TMT) labeling, to reveal temporal responses of suspension-cultured cells to 1 nM and 10 pM PNP at two different time-points post-treatment. Both concentrations yield a distinct differential proteome signature. Since only the higher (1 nM) concentration induces a ROS response, we conclude that the proteome response at the lower concentration reflects a ROS independent response. Furthermore, treatment with 1 nM PNP results in an over-representation of the gene ontology (GO) terms “oxidation-reduction process,” “translation” and “response to salt stress” and this is consistent with a role of AtPNP-A in the adaptation to environmental stress conditions.

  1. Influence of lead upon the plant cell. [Lactuca sativa L

    Energy Technology Data Exchange (ETDEWEB)

    Sekerka, V; Bobak, M

    1975-01-01

    An attempt is made to study the influence of tetramethyl lead upon the mitotic activity of cells, structural changes of the chromosomes, upon the mitotic apparatus and the ultrastructure of the cells in lettuce (Lactuca sativa L.) Tetramethyl lead is an antidetonant additive to the gasoline of automobiles. The authors have found that the Pb ions are toxic for the plant cell, its toxicity increases with an increasing concentration and the prolonged time of action of the Pb solution. Tetramethyl lead influences the cell division causing especially different disturbances of the chromosomes and of the dividing figure during karykinesis and evoking damages of the submicroscopic structure of the plant cell. First of all, the following organels are damaged: the nucleus, the mitochondria, the Golgi apparatus, the endoplasmatic reticulum and the proplastids. A considerable number of formations similar to translosomes arises in the plant cells at the same time.

  2. An introduction to plant cell culture: the future ahead.

    Science.gov (United States)

    Loyola-Vargas, Víctor M; Ochoa-Alejo, Neftalí

    2012-01-01

    Plant cell, tissue, and organ culture (PTC) techniques were developed and established as an experimental necessity for solving important fundamental questions in plant biology, but they currently represent very useful biotechnological tools for a series of important applications such as commercial micropropagation of different plant species, generation of disease-free plant materials, production of haploid and doublehaploid plants, induction of epigenetic or genetic variation for the isolation of variant plants, obtention of novel hybrid plants through the rescue of hybrid embryos or somatic cell fusion from intra- or intergeneric sources, conservation of valuable plant germplasm, and is the keystone for genetic engineering of plants to produce disease and pest resistant varieties, to engineer metabolic pathways with the aim of producing specific secondary metabolites or as an alternative for biopharming. Some other miscellaneous applications involve the utilization of in vitro cultures to test toxic compounds and the possibilities of removing them (bioremediation), interaction of root cultures with nematodes or mycorrhiza, or the use of shoot cultures to maintain plant viruses. With the increased worldwide demand for biofuels, it seems that PTC will certainly be fundamental for engineering different plants species in order to increase the diversity of biofuel options, lower the price marketing, and enhance the production efficiency. Several aspects and applications of PTC such as those mentioned above are the focus of this edition.

  3. Radiation-induced cell death in embryogenic cells of coniferous plants

    International Nuclear Information System (INIS)

    Watanabe, Yoshito; Homma-Takeda, Shino; Yukawa, Masae; Nishimura, Yoshikazu; Sasamoto, Hamako; Takahagi, Masahiko

    2004-01-01

    Reproductive processes are particularly radiosensitive in plant development, which was clearly illustrated in reduction of seed formation in native coniferous plants around Chernobyl after the nuclear accident. For the purpose to investigate the effects of ionizing radiation on embryonic formation in coniferous plants, we used an embryo-derived embryogenic cell culture of a Japanese native coniferous plant, Japanese cedar (Cryplomeria japonica). The embryogenic cells were so radiosensitive that most of the cells died by X-ray irradiation of 5 Gy. This indicated that the embryogenic cells are as radiosensitive as some mammalian cells including lymphocytes. We considered that this type of radiosensitive cell death in the embryogenic cells should be responsible for reproductive damages of coniferous plants by low dose of ionizing radiation. The cell death of the embryogenic cells was characteristic of nuclear DNA fragmentation, which is typically observed in radiation-induced programmed cell death, i.e. apoptosis, in mammalian cells. On the other hand, cell death with nuclear DNA fragmentation did not develop by X-ray irradiation in vegetative cells including meristematic cells of Japanese cedar. This suggests that an apoptosis-like programmed cell death should develop cell-specifically in embryogenic cells by ionizing radiation. The abortion of embryogenic cells may work to prevent transmission of radiation-induced genetic damages to the descendants. (author)

  4. Plant cell engineering: current research, application and future prospects

    International Nuclear Information System (INIS)

    Wang Xunqing; Liu Luxiang

    2008-01-01

    This paper reviewed the current status of basic research in plant cell engineering, highlighted the application of embryo culture, double haploid (DH) technology, protoplast culture and somatic hybridization, somaclonal variation, rapid propagation, and bio-products production of plant-origin, and t he prospects. (authors)

  5. Synthesis and Application of Plant Cell Wall Oligogalactans

    DEFF Research Database (Denmark)

    Andersen, Mathias Christian Franch

    The plant cell walls represent almost 50% of the biomass found in plants and are therefore one of the main targets for biotechnological research. Major motivators are their potential as a renewable energy source for transport fuels, as functional foods, and as a source of raw materials to generate...

  6. Role of proline in cell wall synthesis and plant development and its implications in plant ontogeny

    Directory of Open Access Journals (Sweden)

    POLAVARAPU BILHAN KAVI KISHOR

    2015-07-01

    Full Text Available Proline is a proteogenic amino acid and accumulates both under stress and non-stress conditions as a beneficial solute in plants. Recent discoveries point out that proline plays an important role in plant growth and differentiation across life cycle. It is a key determinant of many cell wall proteins that plays important roles in plant development. The role of extensins (EXTs, arabinogalactan proteins (AGPs and hydroxyproline- and proline-rich proteins (H/PRPs as important components of cell wall proteins that play pivotal roles in cell wall signal transduction cascades, plant development and stress tolerance is discussed in this review. Molecular insights are also provided here into the plausible roles of proline transporters modulating key events in plant development. In addition, the roles of proline during seed developmental transitions including storage protein synthesis are discussed.

  7. Apoptotic induction of skin cancer cell death by plant extracts.

    Science.gov (United States)

    Thuncharoen, Walairat; Chulasiri, Malin; Nilwarangkoon, Sirinun; Nakamura, Yukio; Watanapokasin, Ramida

    2013-01-01

    The aim of the present study was to investigate the effects of plant extracts on cancer apoptotic induction. Human epidermoid carcinoma A431 cell line, obtained from the American Type Culture Collection (ATCC, Manassas, VA), was maintained in Dulbecco's Modified Eagle Medium (DMEM) supplemented with 10% fetal bovine serum (FBS) at 37 degrees C, 5% carbon dioxide (CO2). Plant extract solutions were obtained from S & J international enterprises public company limited. These plant extracts include 50% hydroglycol extracts from Etlingera elatior (Jack) R.M.Smith (torch ginger; EE), Rosa damascene (damask rose; DR) and Rafflesia kerrii Meijer (bua phut; RM). The cell viability, time and dose dependency were determined by MTT (3-(4, 5-Dimethylthiazol-2-yl)-2, 5-diphenyltetrazolium bromide) assay. A431 cells were treated with the plant extracts and stained with Hoechst 33342 fluorescent staining dye. Cell viability was demonstrated by the inhibitory concentration 50% (IC50). The anti-proliferative effects were shown to be dependent on time and dose. Typical characteristics of apoptosis which are cell morphological changes and chromatin condensation were clearly observed. The plant extracts was shown to be effective for anti-proliferation and induction of apoptosis cell death in skin cancer cells. Therefore, mechanisms underlying the cell death and its potential use for treatment of skin cancer will be further studied.

  8. Penium margaritaceum as a model organism for cell wall analysis of expanding plant cells

    DEFF Research Database (Denmark)

    Rydahl, Maja Gro; Fangel, Jonatan Ulrik; Mikkelsen, Maria Dalgaard

    2015-01-01

    organization of the polymeric networks of the cell wall around the protoplast also contributes to the direction of growth, the shape of the cell, and the proper positioning of the cell in a tissue. In essence, plant cell expansion represents the foundation of development. Most studies of plant cell expansion...... have focused primarily upon late divergent multicellular land plants and specialized cell types (e.g., pollen tubes, root hairs). Here, we describe a unicellular green alga, Penium margaritaceum (Penium), which can serve as a valuable model organism for understanding cell expansion and the underlying......The growth of a plant cell encompasses a complex set of subcellular components interacting in a highly coordinated fashion. Ultimately, these activities create specific cell wall structural domains that regulate the prime force of expansion, internally generated turgor pressure. The precise...

  9. Plant response to heavy metals and organic pollutants in cell culture and at whole plant level

    Energy Technology Data Exchange (ETDEWEB)

    Golan-Goldhirsh, A.; Barazani, O. [Ben-Gurion Univ. of The Negev, The Jacob Blaustein Inst. for Desert Research, Albert Katz Dept. of Dryland Biotechnologies, Desert Plant Biotechnology Lab., Sede Boqer Campus (Israel); Nepovim, A.; Soudek, P.; Vanek, T. [Inst. of Organic Chemistry and Biochemistry (Czech Republic); Smrcek, S.; Dufkova, L.; Krenkova, S. [Faculty of Natural Sciences, Charles Univ. (Czech Republic); Yrjala, K. [Univ. of Helsinki, Dept. of Biosciences, Div. of General Microbiology, Helsinki (Finland); Schroeder, P. [Inst. for Soil Ecology, GSF National Research Center for Environment and Health, Neuherberg, Oberschleissheim (Germany)

    2004-07-01

    Background. Increasing awareness in the last decade concerning environmental quality had prompted research into 'green solutions' for soil and water remediation, progressing from laboratory in vitro experiments to pot and field trials. In vitro cell culture experiments provide a convenient system to study basic biological processes, by which biochemical pathways, enzymatic activity and metabolites can be specifically studied. However, it is difficult to relate cell cultures, calli or even hydroponic experiments to the whole plant response to pollutant stress. In the field, plants are exposed to additional a-biotic and biotic factors, which complicate further plant response. Hence, we often see that in vitro selected species perform poorly under soil and field conditions. Soil physical and chemical properties, plant-mycorrhizal association and soil-microbial activity affect the process of contaminant degradation by plants and/or microorganisms, pointing to the importance of pot and field experiments. Objective. This paper is a joint effort of a group of scientists in COST action 837. It represents experimental work and an overview on plant response to environmental stress from in vitro tissue culture to whole plant experiments in soil. Results. Results obtained from in vitro plant tissue cultures and whole plant hydroponic experiments indicate the phytoremediation potential of different plant species and the biochemical mechanisms involved in plant tolerance. In pot experiments, several selected desert plant species, which accumulated heavy metal in hydroponic systems, succeeded in accumulating the heavy metal in soil conditions as well. Conclusions and recommendations. In vitro plant tissue cultures provide a useful experimental system for the study of the mechanisms involved in the detoxification of organic and heavy metal pollutants. However, whole plant experimental systems, as well as hydroponics followed by pot and field trials, are essential when

  10. Structural Studies of Complex Carbohydrates of Plant Cell Walls

    Energy Technology Data Exchange (ETDEWEB)

    Darvill, Alan [Univ. of Georgia, Athens, GA (United States); Hahn, Michael G. [Univ. of Georgia, Athens, GA (United States); O' Neill, Malcolm A. [Univ. of Georgia, Athens, GA (United States); York, William S. [Univ. of Georgia, Athens, GA (United States)

    2015-02-17

    Most of the solar energy captured by land plants is converted into the polysaccharides (cellulose, hemicellulose, and pectin) that are the predominant components of the cell wall. These walls, which account for the bulk of plant biomass, have numerous roles in the growth and development of plants. Moreover, these walls have a major impact on human life as they are a renewable source of biomass, a source of diverse commercially useful polymers, a major component of wood, and a source of nutrition for humans and livestock. Thus, understanding the molecular mechanisms that lead to wall assembly and how cell walls and their component polysaccharides contribute to plant growth and development is essential to improve and extend the productivity and value of plant materials. The proposed research will develop and apply advanced analytical and immunological techniques to study specific changes in the structures and interactions of the hemicellulosic and pectic polysaccharides that occur during differentiation and in response to genetic modification and chemical treatments that affect wall biosynthesis. These new techniques will make it possible to accurately characterize minute amounts of cell wall polysaccharides so that subtle changes in structure that occur in individual cell types can be identified and correlated to the physiological or developmental state of the plant. Successful implementation of this research will reveal fundamental relationships between polysaccharide structure, cell wall architecture, and cell wall functions.

  11. Dynamic changes in transcriptome and cell wall composition underlying brassinosteroid-mediated lignification of switchgrass suspension cells.

    Science.gov (United States)

    Rao, Xiaolan; Shen, Hui; Pattathil, Sivakumar; Hahn, Michael G; Gelineo-Albersheim, Ivana; Mohnen, Debra; Pu, Yunqiao; Ragauskas, Arthur J; Chen, Xin; Chen, Fang; Dixon, Richard A

    2017-01-01

    Plant cell walls contribute the majority of plant biomass that can be used to produce transportation fuels. However, the complexity and variability in composition and structure of cell walls, particularly the presence of lignin, negatively impacts their deconstruction for bioenergy. Metabolic and genetic changes associated with secondary wall development in the biofuel crop switchgrass ( Panicum virgatum ) have yet to be reported. Our previous studies have established a cell suspension system for switchgrass, in which cell wall lignification can be induced by application of brassinolide (BL). We have now collected cell wall composition and microarray-based transcriptome profiles for BL-induced and non-induced suspension cultures to provide an overview of the dynamic changes in transcriptional reprogramming during BL-induced cell wall modification. From this analysis, we have identified changes in candidate genes involved in cell wall precursor synthesis, cellulose, hemicellulose, and pectin formation and ester-linkage generation. We have also identified a large number of transcription factors with expression correlated with lignin biosynthesis genes, among which are candidates for control of syringyl (S) lignin accumulation. Together, this work provides an overview of the dynamic compositional changes during brassinosteroid-induced cell wall remodeling, and identifies candidate genes for future plant genetic engineering to overcome cell wall recalcitrance.

  12. Plant cell wall signalling and receptor-like kinases.

    Science.gov (United States)

    Wolf, Sebastian

    2017-02-15

    Communication between the extracellular matrix and the cell interior is essential for all organisms as intrinsic and extrinsic cues have to be integrated to co-ordinate development, growth, and behaviour. This applies in particular to plants, the growth and shape of which is governed by deposition and remodelling of the cell wall, a rigid, yet dynamic, extracellular network. It is thus generally assumed that cell wall surveillance pathways exist to monitor the state of the wall and, if needed, elicit compensatory responses such as altered expression of cell wall remodelling and biosynthesis genes. Here, I highlight recent advances in the field of cell wall signalling in plants, with emphasis on the role of plasma membrane receptor-like kinase complexes. In addition, possible roles for cell wall-mediated signalling beyond the maintenance of cell wall integrity are discussed. © 2017 The Author(s); published by Portland Press Limited on behalf of the Biochemical Society.

  13. Use of higher plants as screens for toxicity assessment.

    Science.gov (United States)

    Kristen, U

    1997-01-01

    This review deals with the use of entire plants, seedlings, cell suspension cultures and pollen tubes for the estimation of potential toxicity in the environment, and for risk assessment of chemicals and formulations of human relevance. It is shown that the roots of onions and various crop seedlings, as well as in vitro growing pollen tubes of some mono- and dicotyledonous plants, are most frequently used to obtain toxicity data by determination of root and tube growth inhibition. Both roots and pollen tubes are chloroplast free, non-photosynthetic systems and, therefore, with regard to their cytotoxic reactions are closer to vertebrate tissues and cells than are chloroplast-containing plant organs. Root tips and anthers of flower buds are shown to be applicable to genotoxicity screening by microscopic analysis of mitotic or meiotic aberrations during cell division or microspore development, respectively. The processes of mitosis and meiosis are similar in plants and animals. Therefore, meristematic and sporogenic tissues of plants generally show patterns of cytotoxic response similar to those of embryogenic and spermatogenic tissues of vertebrates. The suitability of root tips, cell suspensions and pollen tubes for the investigation of mechanisms of toxic action and for the analysis of structure-activity relationships is also demonstrated. Two plant-based assays, the Allium test and the pollen tube growth test, both currently being evaluated alongside with established mammalian in vivo and in vitro protocols, are emphasized with regard to their potential use as alternatives to animal in vivo toxicity tests. For both assays, preliminary results indicate that the tips of growing roots and the rapidly elongating pollen tubes of certain higher plant species are as reliable as mammalian cell lines for detecting basal cytotoxicity. It is suggested that seeds and pollen grains, in particular, provide easily storable and convenient systems for inexpensive, relatively

  14. DIRECT DISMANTLING OF REPROCESSING PLANT CELLS THE EUREX PLANT EXPERIENCEe2d12c

    International Nuclear Information System (INIS)

    Gili, M.; Troiani, F.; Risoluti, P.

    2003-01-01

    After finishing the reprocessing campaigns in 1970-1983, the EUREX pilot reprocessing plant of ENEA Saluggia Research Center started into a new phase, aiming to materials and irradiated fuel systemation and radioactive wastes conditioning. In 1997 the project ''CORA'' for a vitrification plant for the high and intermediate liquid radioactive wastes started. The ''CORA'' plant will be hosted in some dismantled cells of the EUREX plant, reusing many of the EUREX plant auxiliary systems, duly refurbished, saving money and construction time and avoiding a new nuclear building in the site. Two of the cells that will be reused were part of the EUREX chemical process (solvent recovery and 2nd extraction cycle) and the components were obviously internally contaminated. In 2000 the direct (hands-on) dismantling of one of them started and has been completed in summer 2002; the second one will be dismantled in the next year and then the ''CORA'' plant will be assembled inside the cells. Special care w as taken to avoid spread of contamination in the cells, where ''CORA'' installation activities will start in the next years, during the dismantling process The analysis of data and results collected during the dismantling of the first cell shows that direct dismantling can be achieved with careful choice of tools, procedures and techniques, to reduce volumes of wastes to be disposed and radiological burden

  15. Cellular growth in plants requires regulation of cell wall biochemistry.

    Science.gov (United States)

    Chebli, Youssef; Geitmann, Anja

    2017-02-01

    Cell and organ morphogenesis in plants are regulated by the chemical structure and mechanical properties of the extracellular matrix, the cell wall. The two primary load bearing components in the plant cell wall, the pectin matrix and the cellulose/xyloglucan network, are constantly remodelled to generate the morphological changes required during plant development. This remodelling is regulated by a plethora of loosening and stiffening agents such as pectin methyl-esterases, calcium ions, expansins, and glucanases. The tight spatio-temporal regulation of the activities of these agents is a sine qua non condition for proper morphogenesis at cell and tissue levels. The pectin matrix and the cellulose-xyloglucan network operate in concert and their behaviour is mutually dependent on their chemical, structural and mechanical modifications. Copyright © 2017 Elsevier Ltd. All rights reserved.

  16. The loss of plasma membrane lysopip and an increase of PIP2 result from treatment of carrot cells with fungal enzymes

    International Nuclear Information System (INIS)

    Chen, Q.; Boss, W.F.

    1989-01-01

    The plasma membranes of carrot cells grown in suspension culture are enriched with PIP, lysoPIP, and PIP 2 . To determine whether or not these lipids are involved in signal transduction, we have challenged the cells with a mixture of fungal cellulases, Driselase, and monitored the changes in the phosphoinositides and in the phosphoinositide kinase activity. With cell prelabeled with [ 3 H]inositol, two major changes are observed: (1) lysoPIP decreases 30% compared to the sorbitol control and (2) PIP 2 doubles. There is no increase in IP, IP 2 , or IP 3 . In vitro phosphorylation studies using [γ- 32 P]ATP indicate that the increase in PIP 2 is due in part to activation of the PIP kinase. These data suggest that the role of the polyphosphoinositides in signal transduction in plants may involve activation of the PIP kinase and/or activation of A type phospholipases rather than C type phospholipases

  17. Prospects for advanced coal-fuelled fuel cell power plants

    International Nuclear Information System (INIS)

    Jansen, D.; Laag, P.C. van der; Oudhuis, A.B.J.; Ribberink, J.S.

    1994-01-01

    As part of ECN's in-house R and D programmes on clean energy conversion systems with high efficiencies and low emissions, system assessment studies have been carried out on coal gasification power plants integrated with high-temperature fuel cells (IGFC). The studies also included the potential to reduce CO 2 emissions, and to find possible ways for CO 2 extraction and sequestration. The development of this new type of clean coal technology for large-scale power generation is still far off. A significant market share is not envisaged before the year 2015. To assess the future market potential of coal-fuelled fuel cell power plants, the promise of this fuel cell technology was assessed against the performance and the development of current state-of-the-art large-scale power generation systems, namely the pulverized coal-fired power plants and the integrated coal gasification combined cycle (IGCC) power plants. With the anticipated progress in gas turbine and gas clean-up technology, coal-fuelled fuel cell power plants will have to face severe competition from advanced IGCC power plants, despite their higher efficiency. (orig.)

  18. A quantitative and dynamic model for plant stem cell regulation.

    Directory of Open Access Journals (Sweden)

    Florian Geier

    Full Text Available Plants maintain pools of totipotent stem cells throughout their entire life. These stem cells are embedded within specialized tissues called meristems, which form the growing points of the organism. The shoot apical meristem of the reference plant Arabidopsis thaliana is subdivided into several distinct domains, which execute diverse biological functions, such as tissue organization, cell-proliferation and differentiation. The number of cells required for growth and organ formation changes over the course of a plants life, while the structure of the meristem remains remarkably constant. Thus, regulatory systems must be in place, which allow for an adaptation of cell proliferation within the shoot apical meristem, while maintaining the organization at the tissue level. To advance our understanding of this dynamic tissue behavior, we measured domain sizes as well as cell division rates of the shoot apical meristem under various environmental conditions, which cause adaptations in meristem size. Based on our results we developed a mathematical model to explain the observed changes by a cell pool size dependent regulation of cell proliferation and differentiation, which is able to correctly predict CLV3 and WUS over-expression phenotypes. While the model shows stem cell homeostasis under constant growth conditions, it predicts a variation in stem cell number under changing conditions. Consistent with our experimental data this behavior is correlated with variations in cell proliferation. Therefore, we investigate different signaling mechanisms, which could stabilize stem cell number despite variations in cell proliferation. Our results shed light onto the dynamic constraints of stem cell pool maintenance in the shoot apical meristem of Arabidopsis in different environmental conditions and developmental states.

  19. Mevastatin-induced inhibition of cell growth in avocado suspension ...

    African Journals Online (AJOL)

    Cell suspension cultures were established using soft, friable callus derived from nucellar tissue of 'Hass' avocado (Persea americana Mill.) seed from fruit harvested 190 days after full bloom. Cell cultures were maintained in liquid medium supplemented with naphthalene acetic acid (NAA), isopentenyl adenine (iP) and ...

  20. Plant Cell Division Analyzed by Transient Agrobacterium-Mediated Transformation of Tobacco BY-2 Cells.

    Science.gov (United States)

    Buschmann, Henrik

    2016-01-01

    The continuing analysis of plant cell division will require additional protein localization studies. This is greatly aided by GFP-technology, but plant transformation and the maintenance of transgenic lines can present a significant technical bottleneck. In this chapter I describe a method for the Agrobacterium-mediated genetic transformation of tobacco BY-2 cells. The method allows for the microscopic analysis of fluorescence-tagged proteins in dividing cells in within 2 days after starting a coculture. This transient transformation procedure requires only standard laboratory equipment. It is hoped that this rapid method would aid researchers conducting live-cell localization studies in plant mitosis and cytokinesis.

  1. A Hydroponic Co-cultivation System for Simultaneous and Systematic Analysis of Plant/Microbe Molecular Interactions and Signaling.

    Science.gov (United States)

    Nathoo, Naeem; Bernards, Mark A; MacDonald, Jacqueline; Yuan, Ze-Chun

    2017-07-22

    An experimental design mimicking natural plant-microbe interactions is very important to delineate the complex plant-microbe signaling processes. Arabidopsis thaliana-Agrobacterium tumefaciens provides an excellent model system to study bacterial pathogenesis and plant interactions. Previous studies of plant-Agrobacterium interactions have largely relied on plant cell suspension cultures, the artificial wounding of plants, or the artificial induction of microbial virulence factors or plant defenses by synthetic chemicals. However, these methods are distinct from the natural signaling in planta, where plants and microbes recognize and respond in spatial and temporal manners. This work presents a hydroponic cocultivation system where intact plants are supported by metal mesh screens and cocultivated with Agrobacterium. In this cocultivation system, no synthetic phytohormone or chemical that induces microbial virulence or plant defense is supplemented. The hydroponic cocultivation system closely resembles natural plant-microbe interactions and signaling homeostasis in planta. Plant roots can be separated from the medium containing Agrobacterium, and the signaling and responses of both the plant hosts and the interacting microbes can be investigated simultaneously and systematically. At any given timepoint/interval, plant tissues or bacteria can be harvested separately for various "omics" analyses, demonstrating the power and efficacy of this system. The hydroponic cocultivation system can be easily adapted to study: 1) the reciprocal signaling of diverse plant-microbe systems, 2) signaling between a plant host and multiple microbial species (i.e. microbial consortia or microbiomes), 3) how nutrients and chemicals are implicated in plant-microbe signaling, and 4) how microbes interact with plant hosts and contribute to plant tolerance to biotic or abiotic stresses.

  2. Detection of programmed cell death in plant embryos.

    Science.gov (United States)

    Filonova, Lada H; Suárez, María F; Bozhkov, Peter V

    2008-01-01

    Programmed cell death (PCD) is an integral part of embryogenesis. In plant embryos, PCD functions during terminal differentiation and elimination of the temporary organ, suspensor, as well as during establishment of provascular system. Embryo abortion is another example of embryonic PCD activated at pathological situations and in polyembryonic seeds. Recent studies identified the sequence of cytological events leading to cellular self-destruction in plant embryos. As in most if not all the developmental cell deaths in plants, embryonic PCD is hallmarked by autophagic degradation of the cytoplasm and nuclear disassembly that includes breakdown of the nuclear envelope and DNA fragmentation. The optimized setup of terminal deoxynucleotidyl transferase-mediated dUTP nick end labeling (TUNEL) allows the routine in situ analysis of nuclear DNA fragmentation in plant embryos. This chapter provides step-by-step procedure of how to process embryos for TUNEL and how to combine TUNEL with immunolocalization of the protein of interest.

  3. Nanosecond electric pulses trigger actin responses in plant cells

    International Nuclear Information System (INIS)

    Berghoefer, Thomas; Eing, Christian; Flickinger, Bianca; Hohenberger, Petra; Wegner, Lars H.; Frey, Wolfgang; Nick, Peter

    2009-01-01

    We have analyzed the cellular effects of nanosecond pulsed electrical fields on plant cells using fluorescently tagged marker lines in the tobacco cell line BY-2 and confocal laser scanning microscopy. We observe a disintegration of the cytoskeleton in the cell cortex, followed by contraction of actin filaments towards the nucleus, and disintegration of the nuclear envelope. These responses are accompanied by irreversible permeabilization of the plasma membrane manifest as uptake of Trypan Blue. By pretreatment with the actin-stabilizing drug phalloidin, the detachment of transvacuolar actin from the cell periphery can be suppressed, and this treatment can also suppress the irreversible perforation of the plasma membrane. We discuss these findings in terms of a model, where nanosecond pulsed electric fields trigger actin responses that are key events in the plant-specific form of programmed cell death.

  4. Fuel cell power plants for automotive applications

    Science.gov (United States)

    McElroy, J. F.

    1983-02-01

    While the Solid Polymer Electrolyte (SPE) fuel cell has until recently not been considered competitive with such commercial and industrial energy systems as gas turbine generators and internal combustion engines, electrical current density improvements have markedly improved the capital cost/kW output rating performance of SPE systems. Recent studies of SPE fuel cell applicability to vehicular propulsion have indicated that with adequate development, a powerplant may be produced which will satisfy the performance, size and weight objectives required for viable electric vehicles, and that the cost for such a system would be competitive with alternative advanced power systems.

  5. Oral Delivery of Protein Drugs Bioencapsulated in Plant Cells.

    Science.gov (United States)

    Kwon, Kwang-Chul; Daniell, Henry

    2016-08-01

    Plants cells are now approved by the FDA for cost-effective production of protein drugs (PDs) in large-scale current Good Manufacturing Practice (cGMP) hydroponic growth facilities. In lyophilized plant cells, PDs are stable at ambient temperature for several years, maintaining their folding and efficacy. Upon oral delivery, PDs bioencapsulated in plant cells are protected in the stomach from acids and enzymes but are subsequently released into the gut lumen by microbes that digest the plant cell wall. The large mucosal area of the human intestine offers an ideal system for oral drug delivery. When tags (receptor-binding proteins or cell-penetrating peptides) are fused to PDs, they efficiently cross the intestinal epithelium and are delivered to the circulatory or immune system. Unique tags to deliver PDs to human immune or nonimmune cells have been developed recently. After crossing the epithelium, ubiquitous proteases cleave off tags at engineered sites. PDs are also delivered to the brain or retina by crossing the blood-brain or retinal barriers. This review highlights recent advances in PD delivery to treat Alzheimer's disease, diabetes, hypertension, Gaucher's or ocular diseases, as well as the development of affordable drugs by eliminating prohibitively expensive purification, cold chain and sterile delivery.

  6. Role of the plant cell wall in gravity resistance.

    Science.gov (United States)

    Hoson, Takayuki; Wakabayashi, Kazuyuki

    2015-04-01

    Gravity resistance, mechanical resistance to the gravitational force, is a principal graviresponse in plants, comparable to gravitropism. The cell wall is responsible for the final step of gravity resistance. The gravity signal increases the rigidity of the cell wall via the accumulation of its constituents, polymerization of certain matrix polysaccharides due to the suppression of breakdown, stimulation of cross-link formation, and modifications to the wall environment, in a wide range of situations from microgravity in space to hypergravity. Plants thus develop a tough body to resist the gravitational force via an increase in cell wall rigidity and the modification of growth anisotropy. The development of gravity resistance mechanisms has played an important role in the acquisition of responses to various mechanical stresses and the evolution of land plants. Copyright © 2014 Elsevier Ltd. All rights reserved.

  7. The role of the cell wall in plant immunity

    DEFF Research Database (Denmark)

    Malinovsky, Frederikke Gro; Fangel, Jonatan Ulrik; Willats, William George Tycho

    2014-01-01

    The battle between plants and microbes is evolutionarily ancient, highly complex, and often co-dependent. A primary challenge for microbes is to breach the physical barrier of host cell walls whilst avoiding detection by the plant's immune receptors. While some receptors sense conserved microbial...... features, others monitor physical changes caused by an infection attempt. Detection of microbes leads to activation of appropriate defense responses that then challenge the attack. Plant cell walls are formidable and dynamic barriers. They are constructed primarily of complex carbohydrates joined...... by numerous distinct connection types, and are subject to extensive post-synthetic modification to suit prevailing local requirements. Multiple changes can be triggered in cell walls in response to microbial attack. Some of these are well described, but many remain obscure. The study of the myriad of subtle...

  8. The xylanase inhibitor TAXI-III counteracts the necrotic activity of a Fusarium graminearum xylanase in vitro and in durum wheat transgenic plants.

    Science.gov (United States)

    Moscetti, Ilaria; Faoro, Franco; Moro, Stefano; Sabbadin, Davide; Sella, Luca; Favaron, Francesco; D'Ovidio, Renato

    2015-08-01

    The xylanase inhibitor TAXI-III has been proven to delay Fusarium head blight (FHB) symptoms caused by Fusarium graminearum in transgenic durum wheat plants. To elucidate the molecular mechanism underlying the capacity of the TAXI-III transgenic plants to limit FHB symptoms, we treated wheat tissues with the xylanase FGSG_03624, hitherto shown to induce cell death and hydrogen peroxide accumulation. Experiments performed on lemmas of flowering wheat spikes and wheat cell suspension cultures demonstrated that pre-incubation of xylanase FGSG_03624 with TAXI-III significantly decreased cell death. Most interestingly, a reduced cell death relative to control non-transgenic plants was also obtained by treating, with the same xylanase, lemmas of TAXI-III transgenic plants. Molecular modelling studies predicted an interaction between the TAXI-III residue H395 and residues E122 and E214 belonging to the active site of xylanase FGSG_03624. These results provide, for the first time, clear indications in vitro and in planta that a xylanase inhibitor can prevent the necrotic activity of a xylanase, and suggest that the reduced FHB symptoms on transgenic TAXI-III plants may be a result not only of the direct inhibition of xylanase activity secreted by the pathogen, but also of the capacity of TAXI-III to avoid host cell death. © 2014 BSPP AND JOHN WILEY & SONS LTD.

  9. Gene Delivery into Plant Cells for Recombinant Protein Production

    Directory of Open Access Journals (Sweden)

    Qiang Chen

    2015-01-01

    Full Text Available Recombinant proteins are primarily produced from cultures of mammalian, insect, and bacteria cells. In recent years, the development of deconstructed virus-based vectors has allowed plants to become a viable platform for recombinant protein production, with advantages in versatility, speed, cost, scalability, and safety over the current production paradigms. In this paper, we review the recent progress in the methodology of agroinfiltration, a solution to overcome the challenge of transgene delivery into plant cells for large-scale manufacturing of recombinant proteins. General gene delivery methodologies in plants are first summarized, followed by extensive discussion on the application and scalability of each agroinfiltration method. New development of a spray-based agroinfiltration and its application on field-grown plants is highlighted. The discussion of agroinfiltration vectors focuses on their applications for producing complex and heteromultimeric proteins and is updated with the development of bridge vectors. Progress on agroinfiltration in Nicotiana and non-Nicotiana plant hosts is subsequently showcased in context of their applications for producing high-value human biologics and low-cost and high-volume industrial enzymes. These new advancements in agroinfiltration greatly enhance the robustness and scalability of transgene delivery in plants, facilitating the adoption of plant transient expression systems for manufacturing recombinant proteins with a broad range of applications.

  10. Phenotype-Based Screening of Small Molecules to Modify Plant Cell Walls Using BY-2 Cells.

    Science.gov (United States)

    Okubo-Kurihara, Emiko; Matsui, Minami

    2018-01-01

    The plant cell wall is an important and abundant biomass with great potential for use as a modern recyclable resource. For effective utilization of this cellulosic biomass, its ability to degrade efficiently is key point. With the aim of modifying the cell wall to allow easy decomposition, we used chemical biological technology to alter its structure. As a first step toward evaluating the chemicals in the cell wall we employed a phenotype-based approach using high-throughput screening. As the plant cell wall is essential in determining cell morphology, phenotype-based screening is particularly effective in identifying compounds that bring about alterations in the cell wall. For rapid and reproducible screening, tobacco BY-2 cell is an excellent system in which to observe cell morphology. In this chapter, we provide a detailed chemical biological methodology for studying cell morphology using tobacco BY-2 cells.

  11. Quantification of plant cell coupling with live-cell microscopy

    DEFF Research Database (Denmark)

    Liesche, Johannes; Schulz, Alexander

    2015-01-01

    by confocal microscopy, loaded tracer is activated by UV illumination in a target cell and its spread to neighboring cells monitored. When combined with high-speed acquisition by resonant scanning or spinning disc confocal microscopy, the high signal-to-noise ratio of photoactivation allows collection...

  12. [Effective productions of plant secondary metabolites having antitumor activity by plant cell and tissue cultures].

    Science.gov (United States)

    Taniguchi, Shoko

    2005-06-01

    Methods for the effective production of plant secondary metabolites with antitumor activity using plant cell and tissue cultures were developed. The factors in tannin productivity were investigated using culture strains producing different types of hydrolyzable tannins, i.e., gallotannins (mixture of galloylglucoses), ellagi-, and dehydroellagitannins. Production of ellagi- and dehydroellagitannins was affected by the concentrations and ratio of nitrogen sources in the medium. The formation of oligomeric ellagitannins in shoots of Oenothera tetraptera was correlated with the differentiation of tissues. Cultured cells of Eriobotrya japonica producing ursane- and oleanane-type triterpenes with antitumor activities were also established.

  13. Protective Effects of Tormentic Acid, a Major Component of Suspension Cultures of Eriobotrya japonica Cells, on Acetaminophen-Induced Hepatotoxicity in Mice

    Directory of Open Access Journals (Sweden)

    Wen-Ping Jiang

    2017-05-01

    Full Text Available An acetaminophen (APAP overdose can cause hepatotoxicity and lead to fatal liver damage. The hepatoprotective effects of tormentic acid (TA on acetaminophen (APAP-induced liver damage were investigated in mice. TA was intraperitoneally (i.p. administered for six days prior to APAP administration. Pretreatment with TA prevented the elevation of serum aspartate aminotransferase (AST, alanine aminotransferase (ALT, total bilirubin (T-Bil, total cholesterol (TC, triacylglycerol (TG, and liver lipid peroxide levels in APAP-treated mice and markedly reduced APAP-induced histological alterations in liver tissues. Additionally, TA attenuated the APAP-induced production of nitric oxide (NO, reactive oxygen species (ROS, tumor necrosis factor-alpha (TNF-α, interleukin-1beta (IL-1β, and IL-6. Furthermore, the Western blot analysis showed that TA blocked the protein expression of inducible NO synthase (iNOS and cyclooxygenase-2 (COX-2, as well as the inhibition of nuclear factor-kappa B (NF-κB and mitogen-activated protein kinases (MAPKs activation in APAP-injured liver tissues. TA also retained the superoxidase dismutase (SOD, glutathione peroxidase (GPx, and catalase (CAT in the liver. These results suggest that the hepatoprotective effects of TA may be related to its anti-inflammatory effect by decreasing thiobarbituric acid reactive substances (TBARS, iNOS, COX-2, TNF-α, IL-1β, and IL-6, and inhibiting NF-κB and MAPK activation. Antioxidative properties were also observed, as shown by heme oxygenase-1 (HO-1 induction in the liver, and decreases in lipid peroxides and ROS. Therefore, TA may be a potential therapeutic candidate for the prevention of APAP-induced liver injury by inhibiting oxidative stress and inflammation.

  14. Combined measurement of growth and differentiation in suspension cultures of purified human CD34-positive cells enables a detailed analysis of myelopoiesis

    NARCIS (Netherlands)

    Kerst, J. M.; Slaper-Cortenbach, I. C.; von dem Borne, A. E.; van der Schoot, C. E.; van Oers, R. H.

    1992-01-01

    In this study we have made a detailed analysis of growth factor (granulocyte-macrophage colony-stimulating factor [GM-CSF], granulocyte colony-stimulating factor [G-CSF], and macrophage colony-stimulating factor [M-CSF])-induced proliferation and differentiation of highly purified CD34+ committed

  15. Excretion of polyamines in alfalfa and tobacco suspension-cultured cells and its possible role in maintenance of intracellular polyamine contents

    Czech Academy of Sciences Publication Activity Database

    Cvikrová, Milena; Gemperlová, Lenka; Eder, Josef; Zažímalová, Eva

    2008-01-01

    Roč. 27, č. 7 (2008), s. 1147-1156 ISSN 0721-7714 R&D Projects: GA AV ČR IAA6038303 Institutional research plan: CEZ:AV0Z50380511 Keywords : Arginine decarboxylase * Diamine oxidase * Ornithine decarboxylase Subject RIV: ED - Physiology Impact factor: 1.946, year: 2008

  16. Melatonin redirects carbohydrates metabolism during sugar starvation in plant cells.

    Science.gov (United States)

    Kobylińska, Agnieszka; Borek, Sławomir; Posmyk, Małgorzata M

    2018-05-01

    Recent studies have shown that melatonin is an important molecule in plant physiology. It seems that the most important is that melatonin efficacy eliminates oxidative stress (direct and indirect antioxidant) and moreover induce plant stress reaction and switch on different defence strategies (preventively and interventively actions). In this report, the impact of exogenous melatonin on carbohydrate metabolism in Nicotiana tabacum L. line Bright Yellow 2 (BY-2) suspension cells during sugar starvation was examined. We analysed starch concentration, α-amylase and PEPCK activity as well as proteolytic activity in culture media. It has been shown that BY-2 cell treatment with 200 nM of melatonin improved viability of sugar-starved cells. It was correlated with higher starch content and phosphoenolpyruvate carboxykinase (PEPCK) activity. The obtained results revealed that exogenous melatonin under specific conditions (stress) can play regulatory role in sugar metabolism, and it may modulate carbohydrate concentration in etiolated BY-2 cells. Moreover, our results confirmed the hypothesis that if the starch is synthesised even in sugar-starved cells, it is highly probable that melatonin shifts the BY-2 cell metabolism on gluconeogenesis pathway and allows for synthesis of carbohydrates from nonsugar precursors, that is amino acids. These points to another defence strategy that was induced by exogenous melatonin applied in plants to overcome adverse environmental conditions. © 2018 John Wiley & Sons A/S. Published by John Wiley & Sons Ltd.

  17. Plant oligoadenylates: enzymatic synthesis, isolation, and biological activities

    International Nuclear Information System (INIS)

    Devash, Y.; Reichman, M.; Sela, I.; Reichenbach, N.L.; Suhadolnik, R.J.

    1985-01-01

    An enzyme that converts [ 3 H, 32 P]ATP, with a 3 H: 32 P ratio of 1:1, to oligoadenylates with the same 3 H: 32 P ratio was increased in plants following treatment with human leukocyte interferon or plant antiviral factor or inoculation with tobacco mosaic virus. The enzyme was extracted from tobacco leaves, callus tissue cultures, or cell suspension cultures. The enzyme, a putative plant oligoadenylate synthetase, was immobilized on poly(rI) . poly(rC)-agarose columns and converted ATP into plant oligoadenylates. These oligoadenylates were displaced from DEAE-cellulose columns with 350 mM KCl buffer, dialyzed, and further purified by high-performance liquid chromatography (HPLC) and DEAE-cellulose gradient chromatography. In all steps of purification, the ratio of 3 H: 32 P in the oligoadenylates remained 1:1. The plant oligoadenylates isolated by displacement with 350 mM KCl had a molecular weight greater than 1000. The plant oligoadenylates had charges of 5- and 6-. HPLC resolved five peaks, three of which inhibited protein synthesis in reticulocyte and wheat germ systems. Partial structural elucidation of the plant oligoadenylates has been determined by enzymatic and chemical treatments. An adenylate with a 3',5'-phosphodiester and/or a pyrophosphoryl linkage with either 3'- or 5'-terminal phosphates is postulated on the basis of treatment of the oligoadenylates with T2 RNase, snake venom phosphodiesterase, and bacterial alkaline phosphatase and acid and alkaline hydrolyses. The plant oligoadenylates at 8 X 10(-7) M inhibit protein synthesis by 75% in lysates from rabbit reticulocytes and 45% in wheat germ cell-free systems

  18. Handbook of plant cell culture. Volume 2. Crop species

    Energy Technology Data Exchange (ETDEWEB)

    Sharp, W.R.; Evans, D.A.; Ammirato, P.V.; Yamada, Y. (eds.)

    1984-01-01

    In this volume the state-of-the-art plant cell culture techniques described in the first volume are applied to several agricultural and horticultural crops. In 21 chapters, they include maize, oats, wheat, beans, red clover and other forage legumes, asparagus, celery, cassava, sweet potato, banana, pawpaw, apple, grapes, conifers, date palm, rubber, sugarcane and tobacco. Each chapter contains (1) detailed protocols to serve as the foundation for current research, (2) a critical review of the literature, and (3) in-depth evaluations of the potential shown by plant cell culture for crop improvement. The history and economic importance of each crop are discussed. This volume also includes an essay, ''Oil from plants'', by M. Calvin.

  19. Hydrodynamic flow in the cytoplasm of plant cells.

    NARCIS (Netherlands)

    Esseling-Ozdoba, A.; Houtman, D.; Lammeren, A.A. van; Eiser, E.; Emons, A.M.C.

    2008-01-01

    Plant cells show myosin-driven organelle movement, called cytoplasmic streaming. Soluble molecules, such as metabolites do not move with motor proteins but by diffusion. However, is all of this streaming active motor-driven organelle transport? Our recent simulation study (Houtman et al., 2007)

  20. Hydrodynamic flow in the cytoplasm of plant cells

    NARCIS (Netherlands)

    Esseling-Ozdoba, A.; Houtman, D.; van Lammeren, A.A.M.; Eiser, E.; Emons, A.M.C.

    2008-01-01

    Plant cells show myosin-driven organelle movement, called cytoplasmic streaming. Soluble molecules, such as metabolites do not move with motor proteins but by diffusion. However, is all of this streaming active motor-driven organelle transport? Our recent simulation study (Houtman et al., 2007)

  1. Hydrodynamic flow in the cytoplasm of plant cells

    NARCIS (Netherlands)

    Esseling-Ozdoba, A.; Houtman, D.; Lammeren, van A.A.M.; Eiser, E.; Emons, A.M.C.

    2008-01-01

    Plant cells show myosin-driven organelle movement, called cytoplasmic streaming. Soluble molecules, such as metabolites do not move with motor proteins but by diffusion. However, is all of this streaming active motor-driven organelle transport? Our recent simulation study ( Houtman et al., 2007 )

  2. Green light for quantitative live-cell imaging in plants

    NARCIS (Netherlands)

    Grossmann, Guido; Krebs, Melanie; Maizel, Alexis; Stahl, Yvonne; Vermeer, Joop E.M.; Ott, Thomas

    2018-01-01

    Plants exhibit an intriguing morphological and physiological plasticity that enables them to thrive in a wide range of environments. To understand the cell biological basis of this unparalleled competence, a number ofmethodologies have been adapted or developed over the last decades that allow

  3. Compost in plant microbial fuel cell for bioelectricity generation

    NARCIS (Netherlands)

    Moqsud, M.A.; Yoshitake, J.; Bushra, Q.S.; Hyodo, M.; Omine, K.; Strik, D.P.B.T.B.

    2015-01-01

    Recycling of organic waste is an important topic in developing countries as well as developed countries. Compost from organic waste has been used for soil conditioner. In this study, an experiment has been carried out to produce green energy (bioelectricity) by using paddy plant microbial fuel cells

  4. Plant Physiology: FERONIA Defends the Cell Walls against Corrosion.

    Science.gov (United States)

    Verger, Stéphane; Hamant, Olivier

    2018-03-05

    A new study uncovers the role of wall sensing and remodeling in the plant response to salt stress, identifying the FERONIA receptor kinase as a key player in that process, likely through direct sensing of cell wall pectins. Copyright © 2018 Elsevier Ltd. All rights reserved.

  5. Measuring the Mechanical Properties of Plant Cell Walls

    Directory of Open Access Journals (Sweden)

    Hannes Vogler

    2015-03-01

    Full Text Available The size, shape and stability of a plant depend on the flexibility and integrity of its cell walls, which, at the same time, need to allow cell expansion for growth, while maintaining mechanical stability. Biomechanical studies largely vanished from the focus of plant science with the rapid progress of genetics and molecular biology since the mid-twentieth century. However, the development of more sensitive measurement tools renewed the interest in plant biomechanics in recent years, not only to understand the fundamental concepts of growth and morphogenesis, but also with regard to economically important areas in agriculture, forestry and the paper industry. Recent advances have clearly demonstrated that mechanical forces play a crucial role in cell and organ morphogenesis, which ultimately define plant morphology. In this article, we will briefly review the available methods to determine the mechanical properties of cell walls, such as atomic force microscopy (AFM and microindentation assays, and discuss their advantages and disadvantages. But we will focus on a novel methodological approach, called cellular force microscopy (CFM, and its automated successor, real-time CFM (RT-CFM.

  6. Thin Cell Layer technology in ornamental plant micropropagation ...

    African Journals Online (AJOL)

    Thin cell layer (TCL) technology originated almost 30 years ago with the controlled development of flowers, roots, shoots and somatic embryos on tobacco pedicel longitudinal TCLs. Since then TCLs have been successfully used in the micropropagation of many ornamental plant species whose previous in vitro ...

  7. The plant cell nucleus: a true arena for the fight between plants and pathogens.

    Science.gov (United States)

    Deslandes, Laurent; Rivas, Susana

    2011-01-01

    Communication between the cytoplasm and the nucleus is a fundamental feature shared by both plant and animal cells. Cellular factors involved in the transport of macromolecules through the nuclear envelope, including nucleoporins, importins and Ran-GTP related components, are conserved among a variety of eukaryotic systems. Interestingly, mutations in these nuclear components compromise resistance signalling, illustrating the importance of nucleocytoplasmic trafficking in plant innate immunity. Indeed, spatial restriction of defence regulators by the nuclear envelope and stimulus-induced nuclear translocation constitute an important level of defence-associated gene regulation in plants. A significant number of effectors from different microbial pathogens are targeted to the plant cell nucleus. In addition, key host factors, including resistance proteins, immunity components, transcription factors and transcriptional regulators shuttle between the cytoplasm and the nucleus, and their level of nuclear accumulation determines the output of the defence response, further confirming the crucial role played by the nucleus during the interaction between plants and pathogens. Here, we discuss recent findings that situate the nucleus at the frontline of the mutual recognition between plants and invading microbes.

  8. Biodegradation of 2,4-dinitrotoluene by different plant species.

    Science.gov (United States)

    Podlipná, Radka; Pospíšilová, Blanka; Vaněk, Tomáš

    2015-02-01

    Over the past century, rapid growth of population, mining and industrialization significantly contributed to extensive soil, air and water contamination. The 2,4-dinitrotoluene (2,4-DNT), used mostly as explosive, belongs to the hazardous xenobiotics. Soils and waters contaminated with 2,4-DNT may be cleaned by phytoremediation using suitable plant species. The ability of crop plants (hemp, flax, sunflower and mustard) to germinate and grow on soils contaminated with 2,4-DNT was compared. Stimulation of their growth was found at 0.252 mg/g 2,4-DNT. The lethal concentration for the growth for these species was around 1 mg/g. In hydropony, the above mentioned species were able to survive 200 mg/l 2,4-DNT, the concentration close to maximal solubility of 2,4-DNT in water. Metabolism of 2,4-DNT was tested using suspension culture of soapwort and reed. The degradation products 2-aminonitrotoluene and 4-aminonitrotoluene were found both in the medium and in the acetone extract of plant cells. The test showed that the toxicity of these metabolites was higher than the toxicity of the parent compound, but 2,4-diaminotoluene, the product of next reduction step, was less toxic in the concentration range tested (0-200 mg/l). Copyright © 2014. Published by Elsevier Inc.

  9. Hypersensitive cell death in plants : its mechanisms and role in plant defense against pathogens

    NARCIS (Netherlands)

    Iakimova, E.T.; Michalczuk, L.; Woltering, E.J.

    2005-01-01

    This review is a recent update in the understanding of the hypersensitive response (HR) of plants with special consideration to the physiological and biochemical determinants in different model systems. Hypersensitive response is reviewed as a form of programmed cell death (PCD) representing one of

  10. Unraveling the response of plant cells to cytotoxic saponins

    Science.gov (United States)

    Balestrazzi, Alma; Macovei, Anca; Tava, Aldo; Avato, Pinarosa; Raimondi, Elena

    2011-01-01

    A wide range of pharmacological properties are ascribed to natural saponins, in addition to their biological activities against herbivores, plant soil-borne pathogens and pests. As for animal cells, the cytotoxicity and the chemopreventive role of saponins are mediated by a complex network of signal transduction pathways which include reactive oxygen species (ROS) and nitric oxide (NO). The involvement of other relevant components of the saponin-related signaling routes, such as the Tumor Necrosis Factor (TNF)α, the interleukin (IL)-6 and the Nuclear Transcription FactorκB (NFκB), has been highlighted in animal cells. By contrast, information concerning the response of plant cells to saponins and the related signal transduction pathways is almost missing. To date, there are only a few common features which link plant and animal cells in their response to saponins, such as the early burst in ROS and NO production and the induction of metallothioneins (MTs), small cysteine-rich, metal-binding proteins. This aspect is discussed in the present paper in view of the recent hypothesis that MTs and NO are part of a novel signal transduction pathway participating in the cell response to oxidative stress. PMID:21673512

  11. Micrasterias as a model system in plant cell biology

    Directory of Open Access Journals (Sweden)

    Ursula Luetz-Meindl

    2016-07-01

    Full Text Available The unicellular freshwater alga Micrasterias denticulata is an exceptional organism due to its extraordinary star-shaped, highly symmetric morphology and has thus attracted the interest of researchers for many decades. As a member of the Streptophyta, Micrasterias is not only genetically closely related to higher land plants but shares common features with them in many physiological and cell biological aspects. These facts, together with its considerable cell size of about 200 µm, its modest cultivation conditions and the uncomplicated accessibility particularly to any microscopic techniques, make Micrasterias a very well suited cell biological plant model system. The review focuses particularly on cell wall formation and composition, dictyosomal structure and function, cytoskeleton control of growth and morphogenesis as well as on ionic regulation and signal transduction. It has been also shown in the recent years that Micrasterias is a highly sensitive indicator for environmental stress impact such as heavy metals, high salinity, oxidative stress or starvation. Stress induced organelle degradation, autophagy, adaption and detoxification mechanisms have moved in the center of interest and have been investigated with modern microscopic techniques such as 3-D- and analytical electron microscopy as well as with biochemical, physiological and molecular approaches. This review is intended to summarize and discuss the most important results obtained in Micrasterias in the last 20 years and to compare the results to similar processes in higher plant cells.

  12. Only in dying, life: programmed cell death during plant development.

    Science.gov (United States)

    Van Hautegem, Tom; Waters, Andrew J; Goodrich, Justin; Nowack, Moritz K

    2015-02-01

    Programmed cell death (PCD) is a fundamental process of life. During the evolution of multicellular organisms, the actively controlled demise of cells has been recruited to fulfil a multitude of functions in development, differentiation, tissue homeostasis, and immune systems. In this review we discuss some of the multiple cases of PCD that occur as integral parts of plant development in a remarkable variety of cell types, tissues, and organs. Although research in the last decade has discovered a number of PCD regulators, mediators, and executers, we are still only beginning to understand the mechanistic complexity that tightly controls preparation, initiation, and execution of PCD as a process that is indispensable for successful vegetative and reproductive development of plants. Copyright © 2014 Elsevier Ltd. All rights reserved.

  13. The bioconversion process of deoxypodophyllotoxin with Linum flavum cell cultures

    NARCIS (Netherlands)

    Koulman, A; Beekman, A.C; Pras, N.; Quax, Wim

    2003-01-01

    The in vitro cell suspension culture of Linum flavum is able to convert high amounts of the 2,7'-cyclolignan deoxypodophyllotoxin into 6-methoxypodophyllotoxin 7-O-glucoside. We studied this conversion in detail by monitoring the intermediates and side-products after feeding different concentrations

  14. Atomic force microscopy stiffness tomography on living Arabidopsis thaliana cells reveals the mechanical properties of surface and deep cell-wall layers during growth.

    Science.gov (United States)

    Radotić, Ksenija; Roduit, Charles; Simonović, Jasna; Hornitschek, Patricia; Fankhauser, Christian; Mutavdžić, Dragosav; Steinbach, Gabor; Dietler, Giovanni; Kasas, Sandor

    2012-08-08

    Cell-wall mechanical properties play a key role in the growth and the protection of plants. However, little is known about genuine wall mechanical properties and their growth-related dynamics at subcellular resolution and in living cells. Here, we used atomic force microscopy (AFM) stiffness tomography to explore stiffness distribution in the cell wall of suspension-cultured Arabidopsis thaliana as a model of primary, growing cell wall. For the first time that we know of, this new imaging technique was performed on living single cells of a higher plant, permitting monitoring of the stiffness distribution in cell-wall layers as a function of the depth and its evolution during the different growth phases. The mechanical measurements were correlated with changes in the composition of the cell wall, which were revealed by Fourier-transform infrared (FTIR) spectroscopy. In the beginning and end of cell growth, the average stiffness of the cell wall was low and the wall was mechanically homogenous, whereas in the exponential growth phase, the average wall stiffness increased, with increasing heterogeneity. In this phase, the difference between the superficial and deep wall stiffness was highest. FTIR spectra revealed a relative increase in the polysaccharide/lignin content. Copyright © 2012 Biophysical Society. Published by Elsevier Inc. All rights reserved.

  15. The endoplasmic reticulum in plant immunity and cell death.

    Science.gov (United States)

    Eichmann, Ruth; Schäfer, Patrick

    2012-01-01

    The endoplasmic reticulum (ER) is a highly dynamic organelle in eukaryotic cells and a major production site of proteins destined for vacuoles, the plasma membrane, or apoplast in plants. At the ER, these secreted proteins undergo multiple processing steps, which are supervised and conducted by the ER quality control system. Notably, processing of secreted proteins can considerably elevate under stress conditions and exceed ER folding capacities. The resulting accumulation of unfolded proteins is defined as ER stress. The efficiency of cells to re-establish proper ER function is crucial for stress adaptation. Besides delivering proteins directly antagonizing and resolving stress conditions, the ER monitors synthesis of immune receptors. This indicates the significance of the ER for the establishment and function of the plant immune system. Recent studies point out the fragility of the entire system and highlight the ER as initiator of programed cell death (PCD) in plants as was reported for vertebrates. This review summarizes current knowledge on the impact of the ER on immune and PCD signaling. Understanding the integration of stress signals by the ER bears a considerable potential to optimize development and to enhance stress resistance of plants.

  16. The endoplasmic reticulum in plant immunity and cell death

    Directory of Open Access Journals (Sweden)

    Patrick eSchäfer

    2012-08-01

    Full Text Available The endoplasmic reticulum (ER is a highly dynamic organelle in eukaryotic cells and a major production site of proteins destined for vacuoles, the plasma membrane or apoplast in plants. At the ER, these secreted proteins undergo multiple processing steps, which are supervised and conducted by the ER quality control system. Notably, processing of secreted proteins can considerably elevate under stress conditions and exceed ER folding capacities. The resulting accumulation of unfolded proteins is defined as ER stress. The efficiency of cells to re-establish proper ER function is crucial for stress adaptation. Besides delivering proteins directly antagonizing and resolving stress conditions, the ER monitors synthesis of immune receptors. This indicates the significance of the ER for the establishment and function of the plant immune system. Recent studies point out the fragility of the entire system and highlight the ER as initiator of programmed cell death (PCD in plants as was reported for vertebrates. This review summarizes current knowledge on the impact of the ER on immune and PCD signalling. Understanding the integration of stress signals by the ER bears a considerable potential to optimize development and to enhance stress resistance of plants.

  17. Hot cell design in the vitrification plant China

    International Nuclear Information System (INIS)

    Jiang Yubo; Wang Guangkai; Zhang Wei; Liang Runan; Dou Yuan

    2015-01-01

    In the area of reprocessing and radioactive waste management, gloveboxes and cells are a kind of non-standard equipments providing an isolated room to operate radioactive material inside, while the operator outside with essential biological shield and protection. The hot cell is a typical one, which could handle high radioactive material with various operating means and tight enclosure. The dissertation is based on Vitrification Plant China, a cooperation project between China and Germany. For the sino-western difference in design philosophy, it was presented how to draft an acceptable design proposal of applicable huge hot cells by analysing the design requirements, such as radioprotection, observation, illumination, remote handling, transportation, maintenance and decontamination. The construction feasibility of hot cells was also approved. Thanks to 3D software Autodesk Inventor, digital hot cell was built to integrate all the interfaces inside, which validated the design by checking the mechanical interference. (author)

  18. Membrane Targeting of P-type ATPases in Plant Cells

    International Nuclear Information System (INIS)

    Harper, Jeffrey F.

    2004-01-01

    How membrane proteins are targeted to specific subcellular locations is a very complex and poorly understood area of research. Our long-term goal is to use P-type ATPases (ion pumps), in a model plant system Arabidopsis, as a paradigm to understand how members of a family of closely related membrane proteins can be targeted to different subcellular locations. The research is divided into two specific aims. The first aim is focused on determining the targeting destination of all 10 ACA-type calcium pumps (Arabidopsis Calcium ATPase) in Arabidopsis. ACAs represent a plant specific-subfamily of plasma membrane-type calcium pumps. In contrast to animals, the plant homologs have been found in multiple membrane systems, including the ER (ACA2), tonoplast (ACA4) and plasma membrane (ACA8). Their high degree of similarity provides a unique opportunity to use a comparative approach to delineate the membrane specific targeting information for each pump. One hypothesis to be tested is that an endomembrane located ACA can be re-directed to the plasma membrane by including targeting information from a plasma membrane isoform, ACA8. Our approach is to engineer domain swaps between pumps and monitor the targeting of chimeric proteins in plant cells using a Green Fluorescence Protein (GFP) as a tag. The second aim is to test the hypothesis that heterologous transporters can be engineered into plants and targeted to the plasma membrane by fusing them to a plasma membrane proton pump. As a test case we are evaluating the targeting properties of fusions made between a yeast sodium/proton exchanger (Sod2) and a proton pump (AHA2). This fusion may potentially lead to a new strategy for engineering salt resistant plants. Together these aims are designed to provide fundamental insights into the biogenesis and function of plant cell membrane systems

  19. Expression of Plant Receptor Kinases in Tobacco BY-2 Cells.

    Science.gov (United States)

    Shinohara, Hidefumi; Matsubayashi, Yoshikatsu

    2017-01-01

    Although more than 600 single-transmembrane receptor kinase genes have been found in the Arabidopsis genome, only a few of them have known physiological functions, and even fewer plant receptor kinases have known specific ligands. Ligand-binding analysis must be operated using the functionally expressed receptor form. However, the relative abundance of native receptor kinase molecules in the plasma membrane is often quite low. Here, we present a method for stable and functional expression of plant receptor kinases in tobacco BY-2 cells that allows preparation of microsomal fractions containing the receptor. This procedure provides a sufficient amount of receptor proteins while maintaining its ligand-binding activities.

  20. Mass spectrometry for characterizing plant cell wall polysaccharides

    Directory of Open Access Journals (Sweden)

    Stefan eBauer

    2012-03-01

    Full Text Available Mass spectrometry is a selective and powerful technique to obtain identification and structural information on compounds present in complex mixtures. Since it requires only small sample amount it is an excellent tool for researchers interested in detecting changes in composition of complex carbohydrates of plants. This mini-review gives an overview of common mass spectrometry techniques applied to the analysis of plant cell wall carbohydrates. It presents examples in which mass spectrometry has been used to elucidate the structure of oligosaccharides derived from hemicelluloses and pectins and illustrates how information on sequence, linkages, branching and modifications are obtained from characteristic fragmentation patterns.

  1. A population balance equation model of aggregation dynamics in Taxus suspension cell cultures.

    Science.gov (United States)

    Kolewe, Martin E; Roberts, Susan C; Henson, Michael A

    2012-02-01

    The nature of plant cells to grow as multicellular aggregates in suspension culture has profound effects on bioprocess performance. Recent advances in the measurement of plant cell aggregate size allow for routine process monitoring of this property. We have exploited this capability to develop a conceptual model to describe changes in the aggregate size distribution that are observed over the course of a Taxus cell suspension batch culture. We utilized the population balance equation framework to describe plant cell aggregates as a particulate system, accounting for the relevant phenomenological processes underlying aggregation, such as growth and breakage. We compared model predictions to experimental data to select appropriate kernel functions, and found that larger aggregates had a higher breakage rate, biomass was partitioned asymmetrically following a breakage event, and aggregates grew exponentially. Our model was then validated against several datasets with different initial aggregate size distributions and was able to quantitatively predict changes in total biomass and mean aggregate size, as well as actual size distributions. We proposed a breakage mechanism where a fraction of biomass was lost upon each breakage event, and demonstrated that even though smaller aggregates have been shown to produce more paclitaxel, an optimum breakage rate was predicted for maximum paclitaxel accumulation. We believe this is the first model to use a segregated, corpuscular approach to describe changes in the size distribution of plant cell aggregates, and represents an important first step in the design of rational strategies to control aggregation and optimize process performance. Copyright © 2011 Wiley Periodicals, Inc.

  2. 1000kW phosphoric acid fuel cell power plant. Outline of the plant

    Energy Technology Data Exchange (ETDEWEB)

    Shinobe, Kenji; Suzuki, Kazuo; Kaneko, Hideo

    1988-02-10

    The outline of the 1000KW phosphoric acid fuel cell power plant, developed as part of the Moonlight plan, was described. The plant was composed of 4 stacks of 260KW DC output. They were devided into two train with 680V and 765A. The generation efficiency of the plant was 40% and more. Steam reforming of natural gas was used. As the fuel, fuel cell exhaust gas was used in composition with the natural gas. The DC-AC inverter had an efficiency of 96%. The capacity of hot water generator and demineralized water plant for cell cooling were 2t/h and 1.6t/h, respectively, and air-system was incorporated. In September of 1987, the plant has succeeded in 1000KW power generation, and put in operation now. Under the 100% loaded condition, each cell had a voltage of 0.7V with little variation, and the current was 200mA/cm/sup 2/. No problems were found in cooling conditions and in the control of interpole differential pressure. The reformer has been operated for 1200h scince its commisioning, and had experiences of 100 times on start up-shut down operations, the reformer also indicated good performances in the gas compositions. The starting time of 8h and the load follow-up rate 10%/min remain as the subjects for shortening. DC-AC conversion was good. The concentration of NOx and the noise level satisfied the target values. (12 figs, 1 tab)

  3. Metabolism of fluoranthene in different plant cell cultures and intact plants

    Energy Technology Data Exchange (ETDEWEB)

    Kolb, M.; Harms, H.

    2000-05-01

    The metabolism of fluoranthene was investigated in 11 cell cultures of different plant species using a [{sup 14}C]-labeled standard. Most species metabolized less than 5% of fluoranthene to soluble metabolites and formed less than 5% nonextractable residues during the standardized 48-h test procedure. Higher metabolic rates were observed in lettuce (Lactuca sativa, 6%), wheat (Tricitum aestivum, 9%), and tomato (Lycopersicon esculentum, 15%). A special high metabolic rate of nearly 50% was determined for the rose species Paul's Scarlet. Chromatographic analysis of metabolites extracted from aseptically grown tomato plants proved that the metabolites detected in the cell cultures were also formed in the intact plants. Metabolites produced in tomato and rose cells from [{sup 14}C]-fluoranthene were conjugated with glucose, glucuronic acid, and other cell components. After acid hydrolyses, the main metabolite of both species was 1-hydroxyfluoranthene as identified by gas chromatography-mass spectrometry and high-performance liquid chromatography with diode array detection. The second metabolite formed by both species was 8-hydroxyfluoranthene. A third metabolite in tomatoes was 3-hydroxyfluoranthene.

  4. Space stress and genome shock in developing plant cells

    Science.gov (United States)

    Krikorian, A. D.

    1996-01-01

    In the present paper I review symptoms of stress at the level of the nucleus in cells of plants grown in space under nonoptimized conditions. It remains to be disclosed to what extent gravity "unloading" in the space environment directly contributes to the low mitotic index and the chromosomal anomalies and damage that is frequently, but not invariably, demonstrable in space-grown plants. Evaluation of the available facts indicates that indirect effects play a major role and that there is a significant biological component to the susceptibility to stress damage equation as well. Much remains to be learned on how to provide strictly controlled, optimal environments for plant growth in space. Only after optimized controls become possible will one be able to attribute any observed space effects to lowered gravity or to other significant but more indirect effects of the space environment.

  5. Secondary Metabolite Localization by Autofluorescence in Living Plant Cells

    Directory of Open Access Journals (Sweden)

    Pascale Talamond

    2015-03-01

    Full Text Available Autofluorescent molecules are abundant in plant cells and spectral images offer means for analyzing their spectra, yielding information on their accumulation and function. Based on their fluorescence characteristics, an imaging approach using multiphoton microscopy was designed to assess localization of the endogenous fluorophores in living plant cells. This method, which requires no previous treatment, provides an effective experimental tool for discriminating between multiple naturally-occurring fluorophores in living-tissues. Combined with advanced Linear Unmixing, the spectral analysis extends the possibilities and enables the simultaneous detection of fluorescent molecules reliably separating overlapping emission spectra. However, as with any technology, the possibility for artifactual results does exist. This methodological article presents an overview of the applications of tissular and intra-cellular localization of these intrinsic fluorophores in leaves and fruits (here for coffee and vanilla. This method will provide new opportunities for studying cellular environments and the behavior of endogenous fluorophores in the intracellular environment.

  6. Integrating fuel cell power systems into building physical plants

    Energy Technology Data Exchange (ETDEWEB)

    Carson, J. [KCI Technologies, Inc., Hunt Valley, MD (United States)

    1996-12-31

    This paper discusses the integration of fuel cell power plants and absorption chillers to cogenerate chilled water or hot water/steam for all weather air conditioning as one possible approach to building system applications. Absorption chillers utilize thermal energy in an absorption based cycle to chill water. It is feasible to use waste heat from fuel cells to provide hydronic heating and cooling. Performance regimes will vary as a function of the supply and quality of waste heat. Respective performance characteristics of fuel cells, absorption chillers and air conditioning systems will define relationships between thermal and electrical load capacities for the combined systems. Specifically, this paper develops thermodynamic relationships between bulk electrical power and cooling/heating capacities for combined fuel cell and absorption chiller system in building applications.

  7. Advanced technologies for plant cell wall evolution and diversity

    DEFF Research Database (Denmark)

    Fangel, Jonatan Ulrik

    Plant cell walls consist of polysaccharides, glycoproteins and phenolic polymers interlinked together in a highly complex network. The detailed analysis of cell walls is challenging because of their inherent complexity and heterogeneity. Also, complex carbohydrates, unlike proteins and nucleotides...... cannot really be synthesised or sequenced. The work described in this thesis is focused to a large extent on the development of a microarray-based high-throughput method for cell wall analysis known as Comprehensive microarray polymer profiling or CoMPP. The procedure uses highly specific molecular...... probes (monoclonal antibodies mAbs and carbohydrate binding modules, CBMs) to rapidly profile polysaccharides across a sample set. During my PhD I have further developed the CoMPP technique and used it for cell wall analysis within the context of a variety of applied and fundamental projects. The data...

  8. Integrating cell biology and proteomic approaches in plants.

    Science.gov (United States)

    Takáč, Tomáš; Šamajová, Olga; Šamaj, Jozef

    2017-10-03

    Significant improvements of protein extraction, separation, mass spectrometry and bioinformatics nurtured advancements of proteomics during the past years. The usefulness of proteomics in the investigation of biological problems can be enhanced by integration with other experimental methods from cell biology, genetics, biochemistry, pharmacology, molecular biology and other omics approaches including transcriptomics and metabolomics. This review aims to summarize current trends integrating cell biology and proteomics in plant science. Cell biology approaches are most frequently used in proteomic studies investigating subcellular and developmental proteomes, however, they were also employed in proteomic studies exploring abiotic and biotic stress responses, vesicular transport, cytoskeleton and protein posttranslational modifications. They are used either for detailed cellular or ultrastructural characterization of the object subjected to proteomic study, validation of proteomic results or to expand proteomic data. In this respect, a broad spectrum of methods is employed to support proteomic studies including ultrastructural electron microscopy studies, histochemical staining, immunochemical localization, in vivo imaging of fluorescently tagged proteins and visualization of protein-protein interactions. Thus, cell biological observations on fixed or living cell compartments, cells, tissues and organs are feasible, and in some cases fundamental for the validation and complementation of proteomic data. Validation of proteomic data by independent experimental methods requires development of new complementary approaches. Benefits of cell biology methods and techniques are not sufficiently highlighted in current proteomic studies. This encouraged us to review most popular cell biology methods used in proteomic studies and to evaluate their relevance and potential for proteomic data validation and enrichment of purely proteomic analyses. We also provide examples of

  9. Two endogenous proteins that induce cell wall extension in plants

    Science.gov (United States)

    McQueen-Mason, S.; Durachko, D. M.; Cosgrove, D. J.

    1992-01-01

    Plant cell enlargement is regulated by wall relaxation and yielding, which is thought to be catalyzed by elusive "wall-loosening" enzymes. By employing a reconstitution approach, we found that a crude protein extract from the cell walls of growing cucumber seedlings possessed the ability to induce the extension of isolated cell walls. This activity was restricted to the growing region of the stem and could induce the extension of isolated cell walls from various dicot stems and the leaves of amaryllidaceous monocots, but was less effective on grass coleoptile walls. Endogenous and reconstituted wall extension activities showed similar sensitivities to pH, metal ions, thiol reducing agents, proteases, and boiling in methanol or water. Sequential HPLC fractionation of the active wall extract revealed two proteins with molecular masses of 29 and 30 kD associated with the activity. Each protein, by itself, could induce wall extension without detectable hydrolytic breakdown of the wall. These proteins appear to mediate "acid growth" responses of isolated walls and may catalyze plant cell wall extension by a novel biochemical mechanism.

  10. Biolistic transformation of tobacco and maize suspension cells using bacterial cells as microprojectiles.

    Science.gov (United States)

    Rasmussen, J L; Kikkert, J R; Roy, M K; Sanford, J C

    1994-01-01

    We have used both Escherichia coli cells and Agrobacterium tumefaciens cells as microprojectiles to deliver DNA into suspension-cultured tobacco (Nicotiana tabacum L. line NT1) cells using a helium powered biolistic device. In addition, E. coli cells were used as microprojectiles for the transformation of suspension-cultured maize (Zea mays cv. Black Mexican Sweet) cells. Pretreating the bacterial cells with phenol at a concentration of 1.0%, and combining the bacterial cells with tungsten particles increased the rates of transformation. In N. tabacum, we obtained hundreds of transient transformants per bombardment, but were unable to recover any stable transformants. In Z. mays we obtained thousands of transient transformants and an average of six stable transformants per bombardment. This difference is discussed.

  11. Vacuolar processing enzyme in plant programmed cell death

    Directory of Open Access Journals (Sweden)

    Noriyuki eHatsugai

    2015-04-01

    Full Text Available Vacuolar processing enzyme (VPE is a cysteine proteinase originally identified as the proteinase responsible for the maturation and activation of vacuolar proteins in plants, and it is known to be an orthologue of animal asparaginyl endopeptidase (AEP/VPE/legumain. VPE has been shown to exhibit enzymatic properties similar to that of caspase 1, which is a cysteine protease that mediates the programmed cell death (PCD pathway in animals. Although there is limited sequence identity between VPE and caspase 1, their predicted three-dimensional structures revealed that the essential amino-acid residues for these enzymes form similar pockets for the substrate peptide YVAD. In contrast to the cytosolic localization of caspases, VPE is localized in vacuoles. VPE provokes vacuolar rupture, initiating the proteolytic cascade leading to PCD in the plant immune response. It has become apparent that the VPE-dependent PCD pathway is involved not only in the immune response, but also in the responses to a variety of stress inducers and in the development of various tissues. This review summarizes the current knowledge on the contribution of VPE to plant PCD and its role in vacuole-mediated cell death, and it also compares VPE with the animal cell death executor caspase 1.

  12. Cell physiology of plants growing in cold environments.

    Science.gov (United States)

    Lütz, Cornelius

    2010-08-01

    The life of plants growing in cold extreme environments has been well investigated in terms of morphological, anatomical, and ecophysiological adaptations. In contrast, long-term cellular or metabolic studies have been performed by only a few groups. Moreover, a number of single reports exist, which often represent just a glimpse of plant behavior. The review draws together the literature which has focused on tissue and cellular adaptations mainly to low temperatures and high light. Most studies have been done with European alpine plants; comparably well studied are only two phanerogams found in the coastal Antarctic. Plant adaptation in northern polar regions has always been of interest in terms of ecophysiology and plant propagation, but nowadays, this interest extends to the effects of global warming. More recently, metabolic and cellular investigations have included cold and UV resistance mechanisms. Low-temperature stress resistance in plants from cold environments reflects the climate conditions at the growth sites. It is now a matter of molecular analyses to find the induced genes and their products such as chaperones or dehydrins responsible for this resistance. Development of plants under snow or pollen tube growth at 0 degrees C shows that cell biology is needed to explain the stability and function of the cytoskeleton. Many results in this field are based on laboratory studies, but several publications show that it is not difficult to study cellular mechanisms with the plants adapted to a natural stress. Studies on high light and UV loads may be split in two parts. Many reports describe natural UV as harmful for the plants, but these studies were mainly conducted by shielding off natural UV (as controls). Other experiments apply additional UV in the field and have had practically no negative impact on metabolism. The latter group is supported by the observations that green overwintering plants increase their flavonoids under snow even in the absence of

  13. Determination of Dynamics of Plant Plasma Membrane Proteins with Fluorescence Recovery and Raster Image Correlation Spectroscopy.

    Science.gov (United States)

    Laňková, Martina; Humpolíčková, Jana; Vosolsobě, Stanislav; Cit, Zdeněk; Lacek, Jozef; Čovan, Martin; Čovanová, Milada; Hof, Martin; Petrášek, Jan

    2016-04-01

    A number of fluorescence microscopy techniques are described to study dynamics of fluorescently labeled proteins, lipids, nucleic acids, and whole organelles. However, for studies of plant plasma membrane (PM) proteins, the number of these techniques is still limited because of the high complexity of processes that determine the dynamics of PM proteins and the existence of cell wall. Here, we report on the usage of raster image correlation spectroscopy (RICS) for studies of integral PM proteins in suspension-cultured tobacco cells and show its potential in comparison with the more widely used fluorescence recovery after photobleaching method. For RICS, a set of microscopy images is obtained by single-photon confocal laser scanning microscopy (CLSM). Fluorescence fluctuations are subsequently correlated between individual pixels and the information on protein mobility are extracted using a model that considers processes generating the fluctuations such as diffusion and chemical binding reactions. As we show here using an example of two integral PM transporters of the plant hormone auxin, RICS uncovered their distinct short-distance lateral mobility within the PM that is dependent on cytoskeleton and sterol composition of the PM. RICS, which is routinely accessible on modern CLSM instruments, thus represents a valuable approach for studies of dynamics of PM proteins in plants.

  14. Arabinogalactan-proteins stimulate somatic embryogenesis and plant propagation of Pelargonium sidoides.

    Science.gov (United States)

    Duchow, Stefanie; Dahlke, Renate I; Geske, Thomas; Blaschek, Wolfgang; Classen, Birgit

    2016-11-05

    Root extracts of the medicinal plant Pelargonium sidoides, native to South Africa, are used globally for the treatment of common cold and cough. Due to an increasing economic commercialization of P. sidoides remedies, wild collections of root material should be accompanied by effective methods for plant propagation like somatic embryogenesis. Based on this, the influence of arabinogalactan-proteins (AGPs) on somatic embryogenesis and plant propagation of P. sidoides has been investigated. High-molecular weight AGPs have been isolated from dried roots as well as from cell cultures of P. sidoides with yields between 0.1% and 0.9%, respectively. AGPs are characterized by a 1,3-linked Galp backbone, branched at C6 to 1,6-linked Galp side chains terminated by Araf and to a minor extent by GlcpA, Galp or Rhap. Treatment of explants of P. sidoides with AGPs from roots or suspension culture over 5.5 weeks resulted in effective stimulation of somatic embryo development and plant regeneration. Copyright © 2016. Published by Elsevier Ltd.

  15. Anhydrobiosis and programmed cell death in plants: Commonalities and Differences

    Directory of Open Access Journals (Sweden)

    Samer Singh

    2015-05-01

    Full Text Available Anhydrobiosis is an adaptive strategy of certain organisms or specialised propagules to survive in the absence of water while programmed cell death (PCD is a finely tuned cellular process of the selective elimination of targeted cell during developmental programme and perturbed biotic and abiotic conditions. Particularly during water stress both the strategies serve single purpose i.e., survival indicating PCD may also function as an adaptive process under certain conditions. During stress conditions PCD cause targeted cells death in order to keep the homeostatic balance required for the organism survival, whereas anhydrobiosis suspends cellular metabolic functions mimicking a state similar to death until reestablishment of the favourable conditions. Anhydrobiosis is commonly observed among organisms that have ability to revive their metabolism on rehydration after removal of all or almost all cellular water without damage. This feature is widely represented in terrestrial cyanobacteria and bryophytes where it is very common in both vegetative and reproductive stages of life-cycle. In the course of evolution, with the development of advanced vascular system in higher plants, anhydrobiosis was gradually lost from the vegetative phase of life-cycle. Though it is retained in resurrection plants that primarily belong to thallophytes and a small group of vascular angiosperm, it can be mostly found restricted in orthodox seeds of higher plants. On the contrary, PCD is a common process in all eukaryotes from unicellular to multicellular organisms including higher plants and mammals. In this review we discuss physiological and biochemical commonalities and differences between anhydrobiosis and PCD.

  16. Plant cell nucleolus as a hot spot for iron.

    Science.gov (United States)

    Roschzttardtz, Hannetz; Grillet, Louis; Isaure, Marie-Pierre; Conéjéro, Geneviève; Ortega, Richard; Curie, Catherine; Mari, Stéphane

    2011-08-12

    Many central metabolic processes require iron as a cofactor and take place in specific subcellular compartments such as the mitochondrion or the chloroplast. Proper iron allocation in the different organelles is thus critical to maintain cell function and integrity. To study the dynamics of iron distribution in plant cells, we have sought to identify the different intracellular iron pools by combining three complementary imaging approaches, histochemistry, micro particle-induced x-ray emission, and synchrotron radiation micro X-ray fluorescence. Pea (Pisum sativum) embryo was used as a model in this study because of its large cell size and high iron content. Histochemical staining with ferrocyanide and diaminobenzidine (Perls/diaminobenzidine) strongly labeled a unique structure in each cell, which co-labeled with the DNA fluorescent stain DAPI, thus corresponding to the nucleus. The unexpected presence of iron in the nucleus was confirmed by elemental imaging using micro particle-induced x-ray emission. X-ray fluorescence on cryo-sectioned embryos further established that, quantitatively, the iron concentration found in the nucleus was higher than in the expected iron-rich organelles such as plastids or vacuoles. Moreover, within the nucleus, iron was particularly accumulated in a subcompartment that was identified as the nucleolus as it was shown to transiently disassemble during cell division. Taken together, our data uncover an as yet unidentified although abundant iron pool in the cell, which is located in the nuclei of healthy, actively dividing plant tissues. This result paves the way for the discovery of a novel cellular function for iron related to nucleus/nucleolus-associated processes.

  17. Fuel Cell Balance-of-Plant Reliability Testbed Project

    Energy Technology Data Exchange (ETDEWEB)

    Sproat, Vern [Stark State College of Technology, North Canton, OH (United States); LaHurd, Debbie [Lockheed Martin Corp., Oak Ridge, TN (United States)

    2016-10-29

    Reliability of the fuel cell system balance-of-plant (BoP) components is a critical factor that needs to be addressed prior to fuel cells becoming fully commercialized. Failure or performance degradation of BoP components has been identified as a life-limiting factor in fuel cell systems.1 The goal of this project is to develop a series of test beds that will test system components such as pumps, valves, sensors, fittings, etc., under operating conditions anticipated in real Polymer Electrolyte Membrane (PEM) fuel cell systems. Results will be made generally available to begin removing reliability as a roadblock to the growth of the PEM fuel cell industry. Stark State College students participating in the project, in conjunction with their coursework, have been exposed to technical knowledge and training in the handling and maintenance of hydrogen, fuel cells and system components as well as component failure modes and mechanisms. Three test beds were constructed. Testing was completed on gas flow pumps, tubing, and pressure and temperature sensors and valves.

  18. Life cycle analysis of photovoltaic cell and wind power plants

    International Nuclear Information System (INIS)

    Uchiyama, Yohji

    1997-01-01

    The paper presents life cycle analyses of net energy and CO 2 emissions on photovoltaic cell and wind power generation plants. Energy requirements associated with a plant are estimated for producing materials, manufacturing equipment, constructing facilities, acid operating plants. Energy ratio and net supplied energy are calculated by the process energy analysis that examines the entire energy inventory of input and output during life time of a plant. Life cycle CO 2 emission can also be calculated from the energy requirements obtained by the net energy analysis. The emission also includes greenhouse effect equivalent to CO 2 emission of methane gas leakage at a mining as well as CO 2 emissions from fossil fuel combustion during generating electricity, natural gas treatment at an extracting well and cement production in industry. The commercially available and future-commercial technologies are dealt with in the study. Regarding PV technologies, two different kinds of installation are investigated; roof-top typed installation of residential houses and ground installation of electric utilities. (author)

  19. The cell death factor, cell wall elicitor of rice blast fungus (Magnaporthe grisea) causes metabolic alterations including GABA shunt in rice cultured cells

    OpenAIRE

    Takahashi, Hideyuki; Matsumura, Hideo; Kawai-Yamada, Maki; Uchimiya, Hirofumi

    2008-01-01

    An elicitor derived from the cell wall of rice blast fungus (Magnaporthe grisea) causes cell death in suspension cultured cells of rice (Oryza sativa L.). To elucidate the role of M. grisea elicitor on metabolic pathway of rice cells, we performed metabolite profiling using capillary electrophoresis-mass spectrometry (CE/MS). Treatment with M. grisea elicitor increased the amounts of antioxidants and free amino acids and decreased the amount of metabolites in the tricarboxylic acid (TCA) cycl...

  20. Actin based processes that could determine the cytoplasmic architecture of plant cells

    NARCIS (Netherlands)

    Honing, van der H.S.; Emons, A.M.C.; Ketelaar, M.J.

    2007-01-01

    Actin polymerisation can generate forces that are necessary for cell movement, such as the propulsion of a class of bacteria, including Listeria, and the protrusion of migrating animal cells. Force generation by the actin cytoskeleton in plant cells has not been studied. One process in plant cells

  1. Single guard cell recordings in intact plants : light-induced hyperpolarization of the plasma membrane

    NARCIS (Netherlands)

    Roelfsema, MRG; Steinmeyer, R; Staal, M; Hedrich, R

    Guard cells are electrically isolated from other plant cells and therefore offer the unique possibility to conduct current- and voltage-clamp recordings on single cells in an intact plant. Guard cells in their natural environment were impaled with double-barreled electrodes and found to exhibit

  2. A radioimmunoassay for lignin in plant cell walls

    International Nuclear Information System (INIS)

    Dawley, R.M.

    1989-01-01

    Lignin detection and determination in herbaceous tissue requires selective, specific assays which are not currently available. A radioimmunoassay (RIA) was developed to study lignin metabolism in these tissues. A β-aryl ether lignin model compound was synthesized, linked to keyhole limpet hemocyanin using a water-soluble carbodiimide, and injected into rabbits. The highest titer of the antiserum obtained was 34 ηg/mL of model derivatized BSA. An in vitro system was developed to characterize the RIA. The model compound was linked to amino activated polyacrylamide beads to mimic lignin in the cell walls. 125 I Radiolabelled protein A was used to detect IgG antibody binding. The RIA was shown in the in vitro system to exhibit saturable binding. The amount of antibody bound decreased when the serum was diluted. Immunoelectrophoresis and competitive binding experiments confirmed that both aromatic rings of the lignin model compound had been antigenic. Chlorogenic acid, a phenolic known to be present in plant cells, did not compete for antibody binding. The RIA was used to measure lignin in milled plant samples and barley seedlings. Antiserum binding to wheat cell walls and stressed barley segments was higher than preimmune serum binding. Antibody binding to stressed barley tissue decreased following NaClO 2 delignification. The RIA was found to be less sensitive than expected, so several avenues for improving the method are discussed

  3. The Arabidopsis synaptotagmin SYTA regulates the cell-to-cell movement of diverse plant viruses

    Directory of Open Access Journals (Sweden)

    Asako eUchiyama

    2014-11-01

    Full Text Available Synaptotagmins are a large gene family in animals that have been extensively characterized due to their role as calcium sensors to regulate synaptic vesicle exocytosis and endocytosis in neurons, and dense core vesicle exocytosis for hormone secretion from neuroendocrine cells. Thought to be exclusive to animals, synaptotagmins have recently been characterized in Arabidopsis thaliana, in which they comprise a five gene family. Using infectivity and leaf-based functional assays, we have shown that Arabidopsis SYTA regulates endocytosis and marks an endosomal vesicle recycling pathway to regulate movement protein-mediated trafficking of the Begomovirus Cabbage leaf curl virus (CaLCuV and the Tobamovirus Tobacco mosaic virus (TMV through plasmodesmata (Lewis and Lazarowitz, 2010. To determine whether SYTA has a central role in regulating the cell-to-cell trafficking of a wider range of diverse plant viruses, we extended our studies here to examine the role of SYTA in the cell-to-cell movement of additional plant viruses that employ different modes of movement, namely the Potyvirus Turnip mosaic virus (TuMV, the Caulimovirus Cauliflower mosaic virus (CaMV and the Tobamovirus Turnip vein clearing virus (TVCV, which in contrast to TMV does efficiently infect Arabidopsis. We found that both TuMV and TVCV systemic infection, and the cell-to-cell trafficking of the their movement proteins, were delayed in the Arabidopsis Col-0 syta-1 knockdown mutant. In contrast, CaMV systemic infection was not inhibited in syta-1. Our studies show that SYTA is a key regulator of plant virus intercellular movement, being necessary for the ability of diverse cell-to-cell movement proteins encoded by Begomoviruses (CaLCuV MP, Tobamoviruses (TVCV and TMV 30K protein and Potyviruses (TuMV P3N-PIPO to alter PD and thereby mediate virus cell-to-cell spread.

  4. Enhanced cardiomyogenesis of human embryonic stem cells by a small molecular inhibitor of p38 MAPK.

    NARCIS (Netherlands)

    Graichen, R.; Xu, X.; Braam, S.R.; Balakrishnan, T.; Norfiza, S.; Sieh, S.; Soo, S.Y.; Tham, S.C.; Mummery, C.L.; Colman, A.; Zweigerdt, R.; Davidson, B.P.

    2008-01-01

    Human embryonic stem cells (hESC) can differentiate to cardiomyocytes in vitro but with generally poor efficiency. Here, we describe a novel method for the efficient generation of cardiomyocytes from hESC in a scalable suspension culture process. Differentiation in serum-free medium conditioned by

  5. Cell-to-cell communication in plants, animals, and fungi: a comparative review.

    Science.gov (United States)

    Bloemendal, Sandra; Kück, Ulrich

    2013-01-01

    Cell-to-cell communication is a prerequisite for differentiation and development in multicellular organisms. This communication has to be tightly regulated to ensure that cellular components such as organelles, macromolecules, hormones, or viruses leave the cell in a precisely organized way. During evolution, plants, animals, and fungi have developed similar ways of responding to this biological challenge. For example, in higher plants, plasmodesmata connect adjacent cells and allow communication to regulate differentiation and development. In animals, two main general structures that enable short- and long-range intercellular communication are known, namely gap junctions and tunneling nanotubes, respectively. Finally, filamentous fungi have also developed specialized structures called septal pores that allow intercellular communication via cytoplasmic flow. This review summarizes the underlying mechanisms for intercellular communication in these three eukaryotic groups and discusses its consequences for the regulation of differentiation and developmental processes.

  6. Direct fuel cell power plants: the final steps to commercialization

    Science.gov (United States)

    Glenn, Donald R.

    Since the last paper presented at the Second Grove Fuel Cell Symposium, the Energy Research Corporation (ERC) has established two commercial subsidiaries, become a publically-held firm, expanded its facilities and has moved the direct fuel cell (DFC) technology and systems significantly closer to commercial readiness. The subsidiaries, the Fuel Cell Engineering Corporation (FCE) and Fuel Cell Manufacturing Corporation (FCMC) are perfecting their respective roles in the company's strategy to commercialize its DFC technology. FCE is the prime contractor for the Santa Clara Demonstration and is establishing the needed marketing, sales, engineering, and servicing functions. FCMC in addition to producing the stacks and stack modules for the Santa Clara demonstration plant is now upgrading its production capability and product yields, and retooling for the final stack scale-up for the commercial unit. ERC has built and operated the tallest and largest capacities-to-date carbonate fuel cell stacks as well as numerous short stacks. While most of these units were tested at ERC's Danbury, Connecticut (USA) R&D Center, others have been evaluated at other domestic and overseas facilities using a variety of fuels. ERC has supplied stacks to Elkraft and MTU for tests with natural gas, and RWE in Germany where coal-derived gas were used. Additional stack test activities have been performed by MELCO and Sanyo in Japan. Information from some of these activities is protected by ERC's license arrangements with these firms. However, permission for limited data releases will be requested to provide the Grove Conference with up-to-date results. Arguably the most dramatic demonstration of carbonate fuel cells in the utility-scale, 2 MW power plant demonstration unit, located in the City of Santa Clara, California. Construction of the unit's balance-of-plant (BOP) has been completed and the installed equipment has been operationally checked. Two of the four DFC stack sub-modules, each

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

    Science.gov (United States)

    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.

  8. Application and efficiency of scintillation for autoradiography of plant cells

    International Nuclear Information System (INIS)

    Olszewska, M.J.; Bilecka, A.; Kuran, H.; Marciniak, K.

    1981-01-01

    The effect of scintillators 2,5-diphenyl-oxazole (PPO) and 1,4-bis[2-(5-phenyl)-oxazolyl]- benzene (POPOP) mixed with PPO at -70 0 C and 22 0 C on the exposure time for the autoradiograms of plant cells incubated with 3 H-thymidine (30 min) or 3 H-uridine (30 min) were compared. The number of grains was greatly enhanced by the scintilliation fluids. The best results were obtained with PPO + POPOP mixture at -70 0 C. (orig.)

  9. Plant cell walls: New insights from ancient species

    DEFF Research Database (Denmark)

    Sørensen, Iben; Willats, William George Tycho

    2008-01-01

    Cell walls are a defining feature of plants and have numerous crucial roles in growth and development. They are also the largest source of terrestrial biomass and have many important industrial applications - ranging from bulk products to functional food ingredients. There is considerable interest......¿4)-linked ß-D-Glcp are joined by occasional (1¿3)-linkages. This mixed linkage glucan (MLG) has been the subject of extensive research because of the economic importance of several Poales species including rice, barley and wheat and because MLG has proven health benefits. The recent discovery of MLG...

  10. Plant cell wall extensibility: connecting plant cell growth with cell wall structure, mechanics, and the action of wall-modifying enzymes

    Energy Technology Data Exchange (ETDEWEB)

    Cosgrove, Daniel J.

    2015-11-25

    The advent of user-friendly instruments for measuring force/deflection curves of plant surfaces at high spatial resolution has resulted in a recent outpouring of reports of the ‘Young's modulus’ of plant cell walls. The stimulus for these mechanical measurements comes from biomechanical models of morphogenesis of meristems and other tissues, as well as single cells, in which cell wall stress feeds back to regulate microtubule organization, auxin transport, cellulose deposition, and future growth directionality. In this article I review the differences between elastic modulus and wall extensibility in the context of cell growth. Some of the inherent complexities, assumptions, and potential pitfalls in the interpretation of indentation force/deflection curves are discussed. Reported values of elastic moduli from surface indentation measurements appear to be 10- to >1000-fold smaller than realistic tensile elastic moduli in the plane of plant cell walls. Potential reasons for this disparity are discussed, but further work is needed to make sense of the huge range in reported values. The significance of wall stress relaxation for growth is reviewed and connected to recent advances and remaining enigmas in our concepts of how cellulose, hemicellulose, and pectins are assembled to make an extensible cell wall. A comparison of the loosening action of α-expansin and Cel12A endoglucanase is used to illustrate two different ways in which cell walls may be made more extensible and the divergent effects on wall mechanics.

  11. Fuel cell power plants for decentralised CHP applications

    International Nuclear Information System (INIS)

    Ohmer, Martin; Mattner, Katja

    2015-01-01

    Fuel cells are the most efficient technology to convert chemical energy into electricity and heat and thus they could have a major impact on reducing fuel consumption, CO 2 and other emissions (NO x , SO x and particulate matter). Fired with natural or biogas and operated with an efficiency of up to 49 % a significant reduction of fuel costs can be achieved in decentralised applications. Combined heat and power (CHP) configurations add value for a wide range of industrial applications. The exhaust heat of approximately 400 C can be utilised for heating purposes and the production of steam. Besides, it can be also fed directly to adsorption cooling systems. With more than 110 fuel cell power plants operating worldwide, this technology is a serious alternative to conventional gas turbines or gas engines.

  12. Why does anatabine, but not nicotine, accumulate in jasmonate-elicited cultured tobacco BY-2 cells?

    Science.gov (United States)

    Shoji, Tsubasa; Hashimoto, Takashi

    2008-08-01

    Suspension-cultured cells of Nicotiana tabacum cv. Bright Yellow-2 (BY-2) grow rapidly in a highly homogenous population and still exhibit the general behavior of plant cells, and thus are often used as model systems in several areas of plant molecular and cellular biology, including secondary metabolism. While the parental tobacco variety synthesizes nicotine as a major alkaloid, the cultured tobacco cells mainly produce a related alkaloid anatabine, instead of nicotine, when elicited with jasmonates. We report here that cultured BY-2 cells scarcely express N-methylputrescine oxidase (MPO) genes even after jasmonate elicitation. MPO is the second enzyme in the biosynthetic pathway that supplies the pyrrolidine moiety of nicotine and nornicotine, but is predicted to be dispensable for the biosynthesis of anatabine, anabasine and anatalline, which do not contain the pyrrolidine moiety. When MPO was overexpressed in tobacco BY-2 cells, nicotine synthesis was dramatically enhanced while anatabine formation was effectively suppressed. As a complementary approach, we suppressed MPO expression by RNA interference in tobacco hairy roots that normally accumulate nicotine. In the MPO-suppressed roots, the contents of anatabine, anabasine and anatalline, as well as N-methylputrescine and putrescine, markedly increased to compensate for suppressed formation of nicotine and nornicotine. These results identify the transcriptional regulation of MPO as a critical rate-limiting step that restricts nicotine formation in cultured tobacco BY-2 cells.

  13. Exocytosis and polarity in plant cells: insights by studying cellulose synthase complexes and the exocyst

    NARCIS (Netherlands)

    Ying Zhang, Ying

    2012-01-01

    The work presented in this thesis covers aspects of exocytosis, plant cell growth and cell wall formation. These processes are strongly linked as cell growth and cell wall formation occur simultaneously and exocytosis is the process that delivers cell wall components to the existing cell wall

  14. Chitin nanofiber elucidates the elicitor activity of polymeric chitin in plants

    Directory of Open Access Journals (Sweden)

    Mayumi eEgusa

    2015-12-01

    Full Text Available Chitin, an N-acetyl-D-glucosamine polymer, is a component of fungal cell walls and a microbe/pathogen-associated molecular pattern that elicits plant defense responses. As polymeric chitin is difficult to handle due to its insolubility in water, many studies on chitin-induced immune responses have used water-soluble low-molecular weight chitin instead. Thus, it is unclear if polymeric chitin can induce resistance. Here, we examined the elicitor activity of chitin nanofiber (CNF of submicron thickness prepared from polymeric chitin. CNF showed a high dispersing ability in water and induced both reactive oxygen species (ROS production and chitin-induced defense-related gene expression in Arabidopsis thaliana seedlings. The Arabidopsis chitin elicitor receptor kinase 1 (Atcerk1 mutant, which is impaired in chitin perception, also failed to respond to CNF. CNF exposure triggered ROS generation in suspension-cultured cells from Oryza sativa. Furthermore, pre-treatment of Arabidopsis leaves with CNF effectively reduced pathogen infection by both the fungus Alternaria brassicicola and the bacterium Pseudomonas syringae pv. tomato DC3000. These results demonstrate that CNF has elicitor activity and will help define the role of polymeric chitin in plant immune responses.

  15. Involvement of plant stem cells or stem cell-like cells in dedifferentiation

    Directory of Open Access Journals (Sweden)

    Fangwei eJiang

    2015-11-01

    Full Text Available Dedifferentiation is the transformation of cells from a given differentiated state to a less differentiated or stem cell-like state. Stem cell-related genes play important roles in dedifferentiation, which exhibits similar histone modification and DNA methylation features to stem cell maintenance. Hence, stem cell-related factors possibly synergistically function to provide a specific niche beneficial to dedifferentiation. During callus formation in Arabidopsis petioles, cells adjacent to procambium cells (stem cell-like cells are dedifferentiated and survive more easily than other cell types. This finding indicates that stem cells or stem cell-like cells may influence the dedifferentiating niche. In this paper, we provide a brief overview of stem cell maintenance and dedifferentiation regulation. We also summarize current knowledge of genetic and epigenetic mechanisms underlying the balance between differentiation and dedifferentiation. Furthermore, we discuss the correlation of stem cells or stem cell-like cells with dedifferentiation.

  16. Plant cell transformation with Agrobacterium tumefaciens under simulated microgravity

    Science.gov (United States)

    Sarnatska, Veresa; Gladun, Hanna; Padalko, Svetlana

    To investigate simulated microgravity (clinorotation) effect on plant cell transformation with Agrobacterium tumefaciens and crown gall formation, the culture of primary explants of potato and Jerusalem artichoke tubers was used. It is found that the efficiency of tumor formation and development in clinorotated explants are considerably reduced. When using the explants isolated from potato tubers clinorotated for 3, 5 and 19 days, drastic reduction of formation and development of crown gall tumors was observed. Conversely, the tumor number and their development increased when potato tubers were clinorotated for one day. As was estimated by us previously, cells of Jerusalem artichoke explants are the most sensitive to agrobacteria on 4-5 h of in vitro culturing and this time corresponds to the certain period of G1-stage of the cell cycle. We have also estimated that this period is characterized by the increase of binding of acridine orange by nuclear chromatin and increase in activity of RNA-polymerase I and II. Inoculation of explants with agrobacteria in this period was the most optimal for transformation and crown gall induction. We estimated that at four - hour clinorotation of explants the intensity of acridine orange binding to nuclei was considerably lower than on 4h in the control. At one-day clinorotation of potato tubers, a considerable increase in template accessibility of chromatin and in activity of RNA-polymerase I and II occurred. These results may serve as an evidence for the ability of plant dormant tissues to respond to microgravity. Another demonstration of dormant tissue response to changed gravity we obtained when investigating pathogenesis-related proteins (PR-proteins). PR-proteins were subjected to nondenaturing PAGE.and we have not found any effect of microgravity on PR-proteins of potato explants with normal or tumorous growth. We may suggest that such response derives from the common effects of two stress factors - wounding and changed

  17. Exploring plant tissue culture in Withania somnifera (L.) Dunal: in vitro propagation and secondary metabolite production.

    Science.gov (United States)

    Shasmita; Rai, Manoj K; Naik, Soumendra K

    2017-12-26

    Withania somnifera (L.) Dunal (family: Solanaceae), commonly known as "Indian Ginseng", is a medicinally and industrially important plant of the Indian subcontinent and other warmer parts of the world. The plant has multi-use medicinal potential and has been listed among 36 important cultivated medicinal plants of India that are in high demand for trade due to its pharmaceutical uses. The medicinal importance of this plant is mainly due to the presence of different types of steroidal lactones- withanolides in the roots and leaves. Owing to low seed viability and poor germination, the conventional propagation of W. somnifera falls short to cater its commercial demands particularly for secondary metabolite production. Therefore, there is a great need to develop different biotechnological approaches through tissue and organ culture for seasonal independent production of plants in large scale which will provide sufficient raw materials of uniform quality for pharmaceutical purposes. During past years, a number of in vitro plant regeneration protocols via organogenesis and somatic embryogenesis and in vitro conservation through synthetic seed based encapsulation technology have been developed for W. somnifera. Several attempts have also been made to standardize the protocol of secondary metabolite production via tissue/organ cultures, cell suspension cultures, and Agrobacterium rhizogenes-mediated transformed hairy root cultures. Employment of plant tissue culture based techniques would provide means for rapid propagation and conservation of this plant species and also provide scope for enhanced production of different bioactive secondary metabolites. The present review provides a comprehensive report on research activities conducted in the area of tissue culture and secondary metabolite production in W. somnifera during the past years. It also discusses the unexplored areas which might be taken into consideration for future research so that the medicinal properties and

  18. Esau's Plant anatomy: meristems, cells, and tissues of the plant body : their structure, function, and development

    National Research Council Canada - National Science Library

    Evert, Ray Franklin; Esau, Katherine; Eichhorn, Susan E

    2006-01-01

    ... . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . xix Chapter 1 Structure and Development of the Plant Body- An Overview . . . . . . . . . . . . . . . . . . . . . . . . 1 Internal Organization of the Plant Body...

  19. Nanobiotechnology meets plant cell biology: Carbon nanotubes as organelle targeting nanocarriers

    KAUST Repository

    Serag, Maged F.; Kaji, Noritada; Habuchi, Satoshi; Bianco, Alberto; Baba, Yoshinobu

    2013-01-01

    For years, nanotechnology has shown great promise in the fields of biomedical and biotechnological sciences and medical research. In this review, we demonstrate its versatility and applicability in plant cell biology studies. Specifically, we discuss the ability of functionalized carbon nanotubes to penetrate the plant cell wall, target specific organelles, probe protein-carrier activity and induce organelle recycling in plant cells. We also, shed light on prospective applications of carbon nanomaterials in cell biology and plant cell transformation. © 2013 The Royal Society of Chemistry.

  20. Iron induction of ferritin synthesis in soybean cell suspensions.

    Science.gov (United States)

    Proudhon, D; Briat, J F; Lescure, A M

    1989-06-01

    In animal cells specialized for iron storage, iron-induced accumulation of ferritin is known to result from a shift of stored mRNA from the ribonucleoprotein fraction to polysomes. Previous reports with bean leaves suggested that in plants iron induction of ferritin synthesis would result from a regulation at the transcriptional level (F van der Mark, F Bienfait, H van der Ende [1983] Biochem Biophys Res Commun 115:463-469). Soybean (Glycine max, cv Mandarin) cell suspension cultures have been used here to support these findings. Ferritin induction is obtained by addition of Fe-citrate to the culture medium. A good correlation is found between cellular iron content and the amount of ferritin accumulation. This protein accumulation corresponds to an increase of in vitro translatable ferritin mRNA. Addition of 4 micrograms actinomycin D per milliliter to the cultures inhibits completely in vivo RNA synthesis, whereas protein synthesis was poorly affected, at least for 24 hours. During the same time, this concentration of actinomycin D strongly inhibits the iron-induced synthesis of ferritin. These results show that in soybean cell cultures, the mechanism of regulation of ferritin synthesis in response to iron does not result from recruitment of preexisting mRNA. They confirm that in plant systems, ferritin synthesis results from increased transcription of the corresponding genes.

  1. Regulation of plant cells, cell walls and development by mechanical signals

    Energy Technology Data Exchange (ETDEWEB)

    Meyerowitz, Elliot M. [California Inst. of Technology (CalTech), Pasadena, CA (United States)

    2016-06-14

    The overall goal of the revised scope of work for the final year of funding was to characterize cell wall biosynthesis in developing cotyledons and in the shoot apical meristem of Arabidopsis thaliana, as a way of learning about developmental control of cell wall biosynthesis in plants, and interactions between cell wall biosynthesis and the microtubule cytoskeleton. The proposed work had two parts – to look at the effect of mutation in the SPIRAL2 gene on microtubule organization and reorganization, and to thoroughly characterize the glycosyltransferase genes expressed in shoot apical meristems by RNA-seq experiments, by in situ hybridization of the RNAs expressed in the meristem, and by antibody staining of the products of the glycosyltransferases in meristems. Both parts were completed; the spiral2 mutant was found to speed microtubule reorientation after ablation of adjacent cells, supporting our hypothesis that reorganization correlates with microtubule severing, the rate of which is increased by the mutation. The glycosyltransferase characterization was completed and published as Yang et al. (2016). Among the new things learned was that primary cell wall biosynthesis is strongly controlled both by cell type, and by stage of cell cycle, implying not only that different, even adjacent, cells can have different sugar linkages in their (nonshared) walls, but also that a surprisingly large proportion of glycosyltransferases is regulated in the cell cycle, and therefore that the cell cycle regulates wall maturation to a degree previously unrecognized.

  2. Protein diffusion in plant cell plasma membranes: The cell-wall corral

    Directory of Open Access Journals (Sweden)

    Alexandre eMartinière

    2013-12-01

    Full Text Available Studying protein diffusion informs us about how proteins interact with their environment. Work on protein diffusion over the last several decades has illustrated the complex nature of biological lipid bilayers. The plasma membrane contains an array of membrane-spanning proteins or proteins with peripheral membrane associations. Maintenance of plasma membrane microstructure can be via physical features that provide intrinsic ordering such as lipid microdomains, or from membrane-associated structures such as the cytoskeleton. Recent evidence indicates, that in the case of plant cells, the cell wall seems to be a major player in maintaining plasma membrane microstructure. This interconnection / interaction between cell-wall and plasma membrane proteins most likely plays an important role in signal transduction, cell growth, and cell physiological responses to the environment.

  3. Protein diffusion in plant cell plasma membranes: the cell-wall corral.

    Science.gov (United States)

    Martinière, Alexandre; Runions, John

    2013-01-01

    Studying protein diffusion informs us about how proteins interact with their environment. Work on protein diffusion over the last several decades has illustrated the complex nature of biological lipid bilayers. The plasma membrane contains an array of membrane-spanning proteins or proteins with peripheral membrane associations. Maintenance of plasma membrane microstructure can be via physical features that provide intrinsic ordering such as lipid microdomains, or from membrane-associated structures such as the cytoskeleton. Recent evidence indicates, that in the case of plant cells, the cell wall seems to be a major player in maintaining plasma membrane microstructure. This interconnection / interaction between cell-wall and plasma membrane proteins most likely plays an important role in signal transduction, cell growth, and cell physiological responses to the environment.

  4. Detoxification of Arsenic by Phytochelatins in Plants1

    Science.gov (United States)

    Schmöger, Marcus E.V.; Oven, Matjaz; Grill, Erwin

    2000-01-01

    As is a ubiquitous element present in the atmosphere as well as in the aquatic and terrestrial environments. Arsenite and arsenate are the major forms of As intoxication, and these anions are readily taken up by plants. Both anions efficiently induce the biosynthesis of phytochelatins (PCs) ([γ-glutamate-cysteine]n-glycine) in vivo and in vitro. The rapid induction of the metal-binding PCs has been observed in cell suspension cultures of Rauvolfia serpentina, in seedlings of Arabidopsis, and in enzyme preparations of Silene vulgaris upon challenge to arsenicals. The rate of PC formation in enzyme preparations was lower compared with Cd-induced biosynthesis, but was accompanied by a prolonged induction phase that resulted finally in higher peptide levels. An approximately 3:1 ratio of the sulfhydryl groups from PCs to As is compatible with reported As-glutathione complexes. The identity of the As-induced PCs and of reconstituted metal-peptide complexes has unequivocally been demonstrated by electrospray ionization mass spectroscopy. Gel filtration experiments and inhibitor studies also indicate a complexation and detoxification of As by the induced PCs. PMID:10712543

  5. Changes in microfilament and focal adhesion distribution with loss of androgen responsiveness in cultured mammary tumor cells

    DEFF Research Database (Denmark)

    Couchman, J R; Yates, J; King, R J

    1981-01-01

    of the cells to grow in suspension culture. All these parameters were documented for androgen-responsive and -unresponsive cells grown in culture, as well as the transition of androgen-responsive to -unresponsive cells when deprived of androgen. The androgen-unresponsive cells had extensive and prominent...... microfilament bundles together with focal adhesions on the lower cell surface and also showed strict anchorage dependence for growth. In contrast, microfilament bundles and focal adhesions were absent from androgen-responsive cells, which furthermore had the ability to grow in suspension culture. Differences......, characteristics of both cell types were visible in the cell populations. However, at the stage where all androgen-responsive characteristics were lost, the cells were no longer androgen sensitive. The loss of androgen responsiveness in Shionogi 115 mouse mammary tumor cells is correlated with changes at the cell...

  6. Assembly and enlargement of the primary cell wall in plants

    Science.gov (United States)

    Cosgrove, D. J.

    1997-01-01

    Growing plant cells are shaped by an extensible wall that is a complex amalgam of cellulose microfibrils bonded noncovalently to a matrix of hemicelluloses, pectins, and structural proteins. Cellulose is synthesized by complexes in the plasma membrane and is extruded as a self-assembling microfibril, whereas the matrix polymers are secreted by the Golgi apparatus and become integrated into the wall network by poorly understood mechanisms. The growing wall is under high tensile stress from cell turgor and is able to enlarge by a combination of stress relaxation and polymer creep. A pH-dependent mechanism of wall loosening, known as acid growth, is characteristic of growing walls and is mediated by a group of unusual wall proteins called expansins. Expansins appear to disrupt the noncovalent bonding of matrix hemicelluloses to the microfibril, thereby allowing the wall to yield to the mechanical forces generated by cell turgor. Other wall enzymes, such as (1-->4) beta-glucanases and pectinases, may make the wall more responsive to expansin-mediated wall creep whereas pectin methylesterases and peroxidases may alter the wall so as to make it resistant to expansin-mediated creep.

  7. Methods of expressing and detecting activity of expansin in plant cells

    Energy Technology Data Exchange (ETDEWEB)

    Hood, Elizabeth E.; Yoon, Sangwoong

    2017-10-10

    A method of expressing heterologous expansin in a plant cell is provided where a nucleic acid molecule encoding expansin is introduced into the plant cell and in an embodiment is operably linked to a promoter preferentially expressing in the seed tissue of the plant, and in another embodiment is linked to a promoter preferentially expressing in the embryo tissue of the seed. An embodiment provides the nucleic acid molecule is operably linked to a second nucleic acid molecule that directs expression to the endoplasmic reticulum, vacuole or cell wall. Plants and plant parts expressing expansin are provided. An assay for detection of expansin activity is also provided.

  8. On the track of transfer cell formation by specialized plant-parasitic nematodes.

    Science.gov (United States)

    Rodiuc, Natalia; Vieira, Paulo; Banora, Mohamed Youssef; de Almeida Engler, Janice

    2014-01-01

    Transfer cells are ubiquitous plant cells that play an important role in plant development as well as in responses to biotic and abiotic stresses. They are highly specialized and differentiated cells playing a central role in the acquisition, distribution and exchange of nutrients. Their unique structural traits are characterized by augmented ingrowths of invaginated secondary wall material, unsheathed by an amplified area of plasma membrane enriched in a suite of solute transporters. Similar morphological features can be perceived in vascular root feeding cells induced by sedentary plant-parasitic nematodes, such as root-knot and cyst nematodes, in a wide range of plant hosts. Despite their close phylogenetic relationship, these obligatory biotrophic plant pathogens engage different approaches when reprogramming root cells into giant cells or syncytia, respectively. Both nematode feeding-cells types will serve as the main source of nutrients until the end of the nematode life cycle. In both cases, these nematodes are able to remarkably maneuver and reprogram plant host cells. In this review we will discuss the structure, function and formation of these specialized multinucleate cells that act as nutrient transfer cells accumulating and synthesizing components needed for survival and successful offspring of plant-parasitic nematodes. Plant cells with transfer-like functions are also a renowned subject of interest involving still poorly understood molecular and cellular transport processes.

  9. On the track of transfer cells formation by specialized plant-parasitic nematodes

    Directory of Open Access Journals (Sweden)

    Natalia eRodiuc

    2014-05-01

    Full Text Available Transfer cells are ubiquitous plant cells that play an important role in plant development as well as in responses to biotic and abiotic stresses. They are highly specialized and differentiated cells playing a central role in the acquisition, distribution and exchange of nutrients. Their unique structural traits are characterized by augmented ingrowths of invaginated secondary wall material, unsheathed by an amplified area of plasma membrane enriched in a suite of solute transporters. Similar morphological features can be perceived in vascular root feeding cells induced by sedentary plant-parasitic nematodes, such as root-knot and cyst nematodes, in a wide range of plant hosts. Despite their close phylogenetic relationship, these obligatory biotrophic plant pathogens engage different approaches when reprogramming root cells into giant cells or syncytia, respectively. Both nematode feeding-cells types will serve as the main source of nutrients until the end of the nematode life cycle. In both cases, these nematodes are able to remarkably maneuver and reprogram plant host cells. In this review we will discuss the structural, functional and morphogenetic characteristics function and formation of these specialized multinucleate cells that act as nutrient transfer cells to accumulate and synthesize components needed for survival and successful offspring of plant-parasitic nematodes. Plant cells with transfer-like functions are also a renowned subject of interest involving still poorly understood molecular and cellular transport processes.

  10. Calpain-Mediated positional information directs cell wall orientation to sustain plant stem cell activity, growth and development

    Science.gov (United States)

    Eukaryotic development and stem cell control depend on the integration of cell positional sensing with cell cycle control and cell wall positioning, yet few factors that directly link these events are known. The DEFECTIVE KERNEL1 (DEK1) gene encoding the unique plant calpain protein is fundamental f...

  11. Experience of in-cell visual inspection using CCD camera in hot cell of Reprocessing Plant

    International Nuclear Information System (INIS)

    Reddy, Padi Srinivas; Amudhu Ramesh Kumar, R.; Geo Mathews, M.; Ravisankar, A.

    2013-01-01

    This paper describes the selection, customization and operating experience of the visual inspection system for the hot cell of a Reprocessing Plant. For process equipment such as fuel chopping machine, dissolver, centrifuge, centrifugal extractors etc., viewing of operations and maintenance using manipulators is required. For this, the service of in-cell camera is essential. The ambience of the hot cell of Compact facility for Reprocessing of Advanced fuels in Lead cell (CORAL) for the reprocessing of fast reactor spent fuel has high gamma radiation and acidic vapors. Black and white Charge Coupled Device (CCD) camera has been used in CORAL incorporating in-house modifications to suit the operating ambient conditions, thereby extending the operating life of the camera. (author)

  12. Zinc-Dependent Protection of Tobacco and Rice Cells From Aluminum-Induced Superoxide-Mediated Cytotoxicity

    Science.gov (United States)

    Lin, Cun; Hara, Ayaka; Comparini, Diego; Bouteau, François; Kawano, Tomonori

    2015-01-01

    Al3+ toxicity in growing plants is considered as one of the major factors limiting the production of crops on acidic soils worldwide. In the last 15 years, it has been proposed that Al3+ toxicity are mediated with distortion of the cellular signaling mechanisms such as calcium signaling pathways, and production of cytotoxic reactive oxygen species (ROS) causing oxidative damages. On the other hand, zinc is normally present in plants at high concentrations and its deficiency is one of the most widespread micronutrient deficiencies in plants. Earlier studies suggested that lack of zinc often results in ROS-mediated oxidative damage to plant cells. Previously, inhibitory action of Zn2+ against lanthanide-induced superoxide generation in tobacco cells have been reported, suggesting that Zn2+ interferes with the cation-induced ROS production via stimulation of NADPH oxidase. In the present study, the effect of Zn2+ on Al3+-induced superoxide generation in the cell suspension cultures of tobacco (Nicotiana tabacum L., cell-line, BY-2) and rice (Oryza sativa L., cv. Nipponbare), was examined. The Zn2+-dependent inhibition of the Al3+-induced oxidative burst was observed in both model cells selected from the monocots and dicots (rice and tobacco), suggesting that this phenomenon (Al3+/Zn2+ interaction) can be preserved in higher plants. Subsequently induced cell death in tobacco cells was analyzed by lethal cell staining with Evans blue. Obtained results indicated that presence of Zn2+ at physiological concentrations can protect the cells by preventing the Al3+-induced superoxide generation and cell death. Furthermore, the regulation of the Ca2+ signaling, i.e., change in the cytosolic Ca2+ ion concentration, and the cross-talks among the elements which participate in the pathway were further explored. PMID:26648960

  13. Plasma membrane protein trafficking in plant-microbe interactions: a plant cell point of view

    Directory of Open Access Journals (Sweden)

    Nathalie eLeborgne-Castel

    2014-12-01

    Full Text Available In order to ensure their physiological and cellular functions, plasma membrane (PM proteins must be properly conveyed from their site of synthesis, i.e. the endoplasmic reticulum, to their final destination, the PM, through the secretory pathway. PM protein homeostasis also relies on recycling and/or degradation, two processes that are initiated by endocytosis. Vesicular membrane trafficking events to and from the PM have been shown to be altered when plant cells are exposed to mutualistic or pathogenic microbes. In this review, we will describe the fine-tune regulation of such alterations, and their consequence in PM protein activity. We will consider the formation of intracellular perimicrobial compartments, the PM protein trafficking machinery of the host, and the delivery or retrieval of signaling and transport proteins such as pattern-recognition receptors, producers of reactive oxygen species, and sugar transporters.

  14. Pectinous cell wall thickenings formation - A common defense strategy of plants to cope with Pb.

    Science.gov (United States)

    Krzesłowska, Magdalena; Rabęda, Irena; Basińska, Aneta; Lewandowski, Michał; Mellerowicz, Ewa J; Napieralska, Anna; Samardakiewicz, Sławomir; Woźny, Adam

    2016-07-01

    Lead, one of the most abundant and hazardous trace metals affecting living organisms, has been commonly detected in plant cell walls including some tolerant plants, mining ecotypes and hyperaccumulators. We have previously shown that in tip growing Funaria sp. protonemata cell wall is remodeled in response to lead by formation of thickenings rich in low-methylesterified pectins (pectin epitope JIM5 - JIM5-P) able to bind metal ions, which accumulate large amounts of Pb. Hence, it leads to the increase of cell wall capacity for Pb compartmentalization. Here we show that diverse plant species belonging to different phyla (Arabidopsis, hybrid aspen, star duckweed), form similar cell wall thickenings in response to Pb. These thickenings are formed in tip growing cells such as the root hairs, and in diffuse growing cells such as meristematic and root cap columella cells of root apices in hybrid aspen and Arabidopsis and in mesophyll cells in star duckweed fronds. Notably, all analyzed cell wall thickenings were abundant in JIM5-P and accumulated high amounts of Pb. In addition, the co-localization of JIM5-P and Pb commonly occurred in these cells. Hence, cell wall thickenings formed the extra compartment for Pb accumulation. In this way plant cells increased cell wall capacity for compartmentalization of this toxic metal, protecting protoplast from its toxicity. As cell wall thickenings occurred in diverse plant species and cell types differing in the type of growth we may conclude that pectinous cell wall thickenings formation is a widespread defense strategy of plants to cope with Pb. Moreover, detection of natural defense strategy, increasing plant cell walls capacity for metal accumulation, reveals a promising direction for enhancing plant efficiency in phytoremediation. Copyright © 2016 Elsevier Ltd. All rights reserved.

  15. Intact plant MRI for the study of cell water relations, membrane permeability, cell-to-cell and long distance water transport

    NARCIS (Netherlands)

    As, van H.

    2007-01-01

    Water content and hydraulic conductivity, including transport within cells, over membranes, cell-to-cell, and long-distance xylem and phloem transport, are strongly affected by plant water stress. By being able to measure these transport processes non-invasely in the intact plant situation in

  16. Survey of Medicinal Plants Used in the Management of Sickle Cell ...

    African Journals Online (AJOL)

    Survey of Medicinal Plants Used in the Management of Sickle Cell Disease by Traditional ... The main method of preparation is by decoction and in most cases, the ... Keywords: Ethnobotany, Sickle Cell Disease, Traditional Medicine, Gbonyin ...

  17. Inhibition of sup 125 I organification and thyroid hormone release by interleukin-1, tumor necrosis factor-alpha, and interferon-gamma in human thyrocytes in suspension culture

    Energy Technology Data Exchange (ETDEWEB)

    Sato, K.; Satoh, T.; Shizume, K.; Ozawa, M.; Han, D.C.; Imamura, H.; Tsushima, T.; Demura, H.; Kanaji, Y.; Ito, Y. (Institute of Clinical Endocrinology, Tokyo (Japan))

    1990-06-01

    To elucidate the mechanism of decreased 131I uptake by the thyroid gland in patients with subacute thyroiditis and painless thyroiditis, human thyroid follicles were cultured with interleukin-1 (IL-1), tumor necrosis factor-alpha (TNF alpha), and/or interferon-gamma (IFN gamma), and the effects of these cytokines on thyroid function were studied in vitro. When human thyrocytes were cultured in RPMI-1640 medium containing 0.5% fetal calf serum and TSH for 5-8 days, the cells incorporated 125I, synthesized de novo (125I)iodotyrosines and (125I)iodothyronines, and secreted (125I)T4 and (125I)T3 into the medium. IL-1 alpha and IL-1 beta inhibited 125I incorporation and (125I)iodothyronine release in a concentration-dependent manner. The minimal inhibitory effect was detected at 10 pg/ml. Electron microscopic examination revealed a marked decrease in lysosome formation in IL-1-treated thyrocytes. TNF alpha and IFN gamma also inhibited thyroid function in a concentration-dependent manner. Furthermore, when thyrocytes were cultured with IL-1, TNF alpha and IFN gamma, these cytokines more than additively inhibited thyroid function. Although the main mechanism of 131I uptake suppression in the thyroid gland in subacute thyroiditis is due to cellular damage and suppression of TSH release, our present findings suggest that IL-1, TNF alpha, and IFN gamma produced in the inflammatory process within the thyroid gland further inhibit iodine incorporation and at least partly account for the decreased 131I uptake by the thyroid gland in destruction-induced hyperthyroidism.

  18. Inhibition of 125I organification and thyroid hormone release by interleukin-1, tumor necrosis factor-alpha, and interferon-gamma in human thyrocytes in suspension culture

    International Nuclear Information System (INIS)

    Sato, K.; Satoh, T.; Shizume, K.; Ozawa, M.; Han, D.C.; Imamura, H.; Tsushima, T.; Demura, H.; Kanaji, Y.; Ito, Y.

    1990-01-01

    To elucidate the mechanism of decreased 131I uptake by the thyroid gland in patients with subacute thyroiditis and painless thyroiditis, human thyroid follicles were cultured with interleukin-1 (IL-1), tumor necrosis factor-alpha (TNF alpha), and/or interferon-gamma (IFN gamma), and the effects of these cytokines on thyroid function were studied in vitro. When human thyrocytes were cultured in RPMI-1640 medium containing 0.5% fetal calf serum and TSH for 5-8 days, the cells incorporated 125I, synthesized de novo [125I]iodotyrosines and [125I]iodothyronines, and secreted [125I]T4 and [125I]T3 into the medium. IL-1 alpha and IL-1 beta inhibited 125I incorporation and [125I]iodothyronine release in a concentration-dependent manner. The minimal inhibitory effect was detected at 10 pg/ml. Electron microscopic examination revealed a marked decrease in lysosome formation in IL-1-treated thyrocytes. TNF alpha and IFN gamma also inhibited thyroid function in a concentration-dependent manner. Furthermore, when thyrocytes were cultured with IL-1, TNF alpha and IFN gamma, these cytokines more than additively inhibited thyroid function. Although the main mechanism of 131I uptake suppression in the thyroid gland in subacute thyroiditis is due to cellular damage and suppression of TSH release, our present findings suggest that IL-1, TNF alpha, and IFN gamma produced in the inflammatory process within the thyroid gland further inhibit iodine incorporation and at least partly account for the decreased 131I uptake by the thyroid gland in destruction-induced hyperthyroidism

  19. Ultrastructural and Molecular Analyses Reveal Enhanced Nucleolar Activity in Medicago truncatula Cells Overexpressing the MtTdp2α Gene

    Science.gov (United States)

    Macovei, Anca; Faè, Matteo; Biggiogera, Marco; de Sousa Araújo, Susana; Carbonera, Daniela; Balestrazzi, Alma

    2018-01-01

    The role of tyrosyl-DNA phosphodiesterase 2 (Tdp2) involved in the repair of 5′-end-blocking DNA lesions is still poorly explored in plants. To gain novel insights, Medicago truncatula suspension cultures overexpressing the MtTdp2α gene (Tdp2α-13C and Tdp2α-28 lines, respectively) and a control (CTRL) line carrying the empty vector were investigated. Transmission electron microscopy (TEM) revealed enlarged nucleoli (up to 44% expansion of the area, compared to CTRL), the presence of nucleolar vacuoles, increased frequency of multinucleolate cells (up to 4.3-fold compared to CTRL) and reduced number of ring-shaped nucleoli in Tdp2α-13C and Tdp2α-28 lines. Ultrastructural data suggesting for enhanced nucleolar activity in MtTdp2α-overexpressing lines were integrated with results from bromouridine incorporation. The latter revealed an increase of labeled transcripts in both Tdp2α-13C and Tdp2α-28 cells, within the nucleolus and in the extra-nucleolar region. MtTdp2α-overexpressing cells showed tolerance to etoposide, a selective inhibitor of DNA topoisomerase II, as evidenced by DNA diffusion assay. TEM analysis revealed etoposide-induced rearrangements within the nucleolus, resembling the nucleolar caps observed in animal cells under transcription impairment. Based on these findings it is evident that MtTdp2α-overexpression enhances nucleolar activity in plant cells. PMID:29868059

  20. Ultrastructural and Molecular Analyses Reveal Enhanced Nucleolar Activity in Medicago truncatula Cells Overexpressing the MtTdp2α Gene

    Directory of Open Access Journals (Sweden)

    Anca Macovei

    2018-05-01

    Full Text Available The role of tyrosyl-DNA phosphodiesterase 2 (Tdp2 involved in the repair of 5′-end-blocking DNA lesions is still poorly explored in plants. To gain novel insights, Medicago truncatula suspension cultures overexpressing the MtTdp2α gene (Tdp2α-13C and Tdp2α-28 lines, respectively and a control (CTRL line carrying the empty vector were investigated. Transmission electron microscopy (TEM revealed enlarged nucleoli (up to 44% expansion of the area, compared to CTRL, the presence of nucleolar vacuoles, increased frequency of multinucleolate cells (up to 4.3-fold compared to CTRL and reduced number of ring-shaped nucleoli in Tdp2α-13C and Tdp2α-28 lines. Ultrastructural data suggesting for enhanced nucleolar activity in MtTdp2α-overexpressing lines were integrated with results from bromouridine incorporation. The latter revealed an increase of labeled transcripts in both Tdp2α-13C and Tdp2α-28 cells, within the nucleolus and in the extra-nucleolar region. MtTdp2α-overexpressing cells showed tolerance to etoposide, a selective inhibitor of DNA topoisomerase II, as evidenced by DNA diffusion assay. TEM analysis revealed etoposide-induced rearrangements within the nucleolus, resembling the nucleolar caps observed in animal cells under transcription impairment. Based on these findings it is evident that MtTdp2α-overexpression enhances nucleolar activity in plant cells.

  1. Catalysts of plant cell wall loosening [version 1; referees: 2 approved

    OpenAIRE

    Daniel J. Cosgrove

    2016-01-01

    The growing cell wall in plants has conflicting requirements to be strong enough to withstand the high tensile forces generated by cell turgor pressure while selectively yielding to those forces to induce wall stress relaxation, leading to water uptake and polymer movements underlying cell wall expansion. In this article, I review emerging concepts of plant primary cell wall structure, the nature of wall extensibility and the action of expansins, family-9 and -12 endoglucanases, family-16 xyl...

  2. Elucidation of the Signal Transduction Pathways Activated by the Plant Natriuretic Peptide AtPNP-A

    KAUST Repository

    Turek, Ilona

    2014-11-01

    Plant natriuretic peptides (PNPs) comprise a novel class of hormones that share some sequence similarity in the active site with their animal analogues that function as regulators of salt and water balance. A PNP present in Arabidopsis thaliana (AtPNP-A) has been assigned a role in abiotic and biotic stress responses, and the recombinant protein has been demonstrated to elicit cyclic guanosine monophosphate (cGMP)-dependent stomatal guard cell opening, regulate ion movements, and induce osmoticum-dependent water uptake. Although the importance of the hormone in maintaining ion and fluid homeostasis has been established, key components of the AtPNP-A-dependent signal transduction pathway remain unknown. Since identification of the binding partners of AtPNP-A, including its receptor(s), is fundamental to understanding the mode of its action at the molecular level, comprehensive protein-protein interaction studies, involving yeast two-hybrid screening, affinity-based assays, protein cross-linking and co-immunoprecipitation followed by mass spectrometric (MS) analyses have been performed. Several candidate binding partners of AtPNP-A identified with at least two independent methods were subsequently expressed as recombinant proteins, purified, and the specificity of their interactions with the recombinant AtPNP-A was verified using surface plasmon resonance. Several specific binary interactants of AtPNP-A were subjected to functional assays aimed at unraveling the consequences of the interactions in planta. These experiments have revealed that reactive oxygen species (ROS) are novel secondary messengers involved in the transduction of AtPNP-A signal in suspension-cultured cells of A. thaliana (Col-0). Further insight into the AtPNP-A dependent signalling events occurring in suspension-cultured cells in ROS-dependent or ROS-independent manner have been obtained from the large-scale proteomics study employing tandem mass tag (TMT) labelling followed by MS analysis to

  3. Changes in pyridine metabolism profile during growth of trigonelline-forming Lotus japonicus cell cultures.

    Science.gov (United States)

    Yin, Yuling; Matsui, Ayu; Sakuta, Masaaki; Ashihara, Hiroshi

    2008-12-01

    Changes in the profile of pyridine metabolism during growth of cells were investigated using trigonelline-forming suspension-cultured cells of Lotus japonicus. Activity of the de novo and salvage pathways of NAD biosynthesis was estimated from the in situ metabolism of [(3)H] quinolinic acid and [(14)C] nicotinamide. Maximum activity of the de novo pathway for NAD synthesis was found in the exponential growth phase, whereas activity of the salvage pathway was increased in the lag phase of cell growth. Expression profiles of some genes related to pyridine metabolism were examined using the expression sequence tags obtained from the L. japonicus database. Transcript levels of NaPRT and NIC, encoding salvage enzymes, were enhanced in the lag phase of cell growth, whereas the maximum expression of NADS was found in the exponential growth phase. Correspondingly, the activities of the salvage enzymes, nicotinate phosphoribosyltransferase (EC 2.4.2.11) and nicotinamidase (EC 3.5.1.19), increased one day after transfer of the stationary phase cells to the fresh medium. The greatest in situ trigonelline synthesis, both from [(3)H] quinolinic acid and [(14)C] nicotinamide, was found in the stationary phase of cell growth. The role of trigonelline in leguminous plants is discussed.

  4. Sonication reduces the attachment of Salmonella Typhimurium ATCC 14028 cells to bacterial cellulose-based plant cell wall models and cut plant material.

    Science.gov (United States)

    Tan, Michelle S F; Rahman, Sadequr; Dykes, Gary A

    2017-04-01

    This study investigated the removal of bacterial surface structures, particularly flagella, using sonication, and examined its effect on the attachment of Salmonella Typhimurium ATCC 14028 cells to plant cell walls. S. Typhimurium ATCC 14028 cells were subjected to sonication at 20 kHz to remove surface structures without affecting cell viability. Effective removal of flagella was determined by staining flagella of sonicated cells with Ryu's stain and enumerating the flagella remaining by direct microscopic counting. The attachment of sonicated S. Typhimurium cells to bacterial cellulose-based plant cell wall models and cut plant material (potato, apple, lettuce) was then evaluated. Varying concentrations of pectin and/or xyloglucan were used to produce a range of bacterial cellulose-based plant cell wall models. As compared to the non-sonicated controls, sonicated S. Typhimurium cells attached in significantly lower numbers (between 0.5 and 1.0 log CFU/cm 2 ) to all surfaces except to the bacterial cellulose-only composite without pectin and xyloglucan. Since attachment of S. Typhimurium to the bacterial cellulose-only composite was not affected by sonication, this suggests that bacterial surface structures, particularly flagella, could have specific interactions with pectin and xyloglucan. This study indicates that sonication may have potential applications for reducing Salmonella attachment during the processing of fresh produce. Copyright © 2016 Elsevier Ltd. All rights reserved.

  5. Cell cycle and cell death are not necessary for appressorium formation and plant infection in the fungal plant pathogen Colletotrichum gloeosporioides

    Directory of Open Access Journals (Sweden)

    Barhoom Sima

    2008-02-01

    Full Text Available Abstract Background In order to initiate plant infection, fungal spores must germinate and penetrate into the host plant. Many fungal species differentiate specialized infection structures called appressoria on the host surface, which are essential for successful pathogenic development. In the model plant pathogen Magnaporthe grisea completion of mitosis and autophagy cell death of the spore are necessary for appressoria-mediated plant infection; blocking of mitosis prevents appressoria formation, and prevention of autophagy cell death results in non-functional appressoria. Results We found that in the closely related plant pathogen Colletotrichum gloeosporioides, blocking of the cell cycle did not prevent spore germination and appressoria formation. The cell cycle always lagged behind the morphogenetic changes that follow spore germination, including germ tube and appressorium formation, differentiation of the penetrating hypha, and in planta formation of primary hyphae. Nuclear division was arrested following appressorium formation and was resumed in mature appressoria after plant penetration. Unlike in M. grisea, blocking of mitosis had only a marginal effect on appressoria formation; development in hydroxyurea-treated spores continued only for a limited number of cell divisions, but normal numbers of fully developed mature appressoria were formed under conditions that support appressoria formation. Similar results were also observed in other Colletotrichum species. Spores, germ tubes, and appressoria retained intact nuclei and remained viable for several days post plant infection. Conclusion We showed that in C. gloeosporioides the differentiation of infection structures including appressoria precedes mitosis and can occur without nuclear division. This phenomenon was also found to be common in other Colletotrichum species. Spore cell death did not occur during plant infection and the fungus primary infection structures remained viable

  6. Cell wall integrity signaling in plants: "To grow or not to grow that's the question".

    Science.gov (United States)

    Voxeur, Aline; Höfte, Herman

    2016-09-01

    Plants, like yeast, have the ability to monitor alterations in the cell wall architecture that occur during normal growth or in changing environments and to trigger compensatory changes in the cell wall. We discuss how recent advances in our understanding of the cell wall architecture provide new insights into the role of cell wall integrity sensing in growth control. Next we review the properties of membrane receptor-like kinases that have roles in pH control, mechano-sensing and reactive oxygen species accumulation in growing cells and which may be the plant equivalents of the yeast cell wall integrity (CWI) sensors. Finally, we discuss recent findings showing an increasing role for CWI signaling in plant immunity and the adaptation to changes in the ionic environment of plant cells. © The Author 2016. Published by Oxford University Press. All rights reserved. For permissions, please e-mail: journals.permissions@oup.com.

  7. High-resolution solution-state NMR of unfractionated plant cell walls

    Science.gov (United States)

    John Ralph; Fachuang Lu; Hoon Kim; Dino Ress; Daniel J. Yelle; Kenneth E. Hammel; Sally A. Ralph; Bernadette Nanayakkara; Armin Wagner; Takuya Akiyama; Paul F. Schatz; Shawn D. Mansfield; Noritsugu Terashima; Wout Boerjan; Bjorn Sundberg; Mattias Hedenstrom

    2009-01-01

    Detailed structural studies on the plant cell wall have traditionally been difficult. NMR is one of the preeminent structural tools, but obtaining high-resolution solution-state spectra has typically required fractionation and isolation of components of interest. With recent methods for dissolution of, admittedly, finely divided plant cell wall material, the wall can...

  8. Microbial community structure elucidates performance of Glyceria maxima plant microbial fuel cell

    NARCIS (Netherlands)

    Timmers, R.A.; Rothballer, M.; Strik, D.P.B.T.B.; Engel, M.; Schulz, M.; Hartmann, A.; Hamelers, H.V.M.; Buisman, C.J.N.

    2012-01-01

    The plant microbial fuel cell (PMFC) is a technology in which living plant roots provide electron donor, via rhizodeposition, to a mixed microbial community to generate electricity in a microbial fuel cell. Analysis and localisation of the microbial community is necessary for gaining insight into

  9. Dismantling of an alpha contaminated hot cell at the Marcoule Pilot Plant

    International Nuclear Information System (INIS)

    Tachon, M.

    1988-01-01

    For the remodeling of Marcoule Pilot Plant, the cell 82: old unit for plutonium solution purification by extraction, was dismantled. About 42 tons of wastes were evacuated. Some wastes wen decontaminated by mechanical means other wastes with higher residual activity were stored for subsequent processing. The operation shows that dismantling of a hot cell is possible even if incorporated in an operating plant [fr

  10. The Role of Pectin Acetylation in the Organization of Plant Cell Walls

    DEFF Research Database (Denmark)

    Fimognari, Lorenzo

    adopt defined 3D organization to allow their composition/interactions to be tweaked upon developmental need. Failure to build functional cell wall architecture will affect plant growth and resistance to stresses. In this PhD dissertation I explored the role of pectin acetylation in controlling...... wall organization, namely polysaccharides-to-polysaccharides interactions. These results suggest that cell wall acetylation is a mechanism that plants evolved to control cell wall organization. In Manuscript III, we report the characterization of Arabidopsis mutants trichome birefringence like (tbl) 10......All plant cells are surrounded by one or more cell wall layers. The cell wall serves as a stiff mechanical support while it allows cells to expand and provide a protective barrier to invading pathogens. Cell walls are dynamic structures composed of entangled cell wall polysaccharides that must...

  11. Evolution of plant cell wall: Arabinogalactan-proteins from three moss genera show structural differences compared to seed plants.

    Science.gov (United States)

    Bartels, Desirée; Baumann, Alexander; Maeder, Malte; Geske, Thomas; Heise, Esther Marie; von Schwartzenberg, Klaus; Classen, Birgit

    2017-05-01

    Arabinogalactan-proteins (AGPs) are important proteoglycans of plant cell walls. They seem to be present in most, if not all seed plants, but their occurrence and structure in bryophytes is widely unknown and actually the focus of AGP research. With regard to evolution of plant cell wall, we isolated AGPs from the three mosses Sphagnum sp., Physcomitrella patens and Polytrichastrum formosum. The moss AGPs show structural characteristics common for AGPs of seed plants, but also unique features, especially 3-O-methyl-rhamnose (trivial name acofriose) as terminal monosaccharide not found in arabinogalactan-proteins of angiosperms and 1,2,3-linked galactose as branching point never found in arabinogalactan-proteins before. Copyright © 2017 Elsevier Ltd. All rights reserved.

  12. Cell wall integrity, genotoxic injury and PCD dynamics in alfalfa saponin-treated white poplar cells highlight a complex link between molecule structure and activity.

    Science.gov (United States)

    Paparella, Stefania; Tava, Aldo; Avato, Pinarosa; Biazzi, Elisa; Macovei, Anca; Biggiogera, Marco; Carbonera, Daniela; Balestrazzi, Alma

    2015-03-01

    In the present work, eleven saponins and three sapogenins purified from Medicago sativa were tested for their cytotoxicity against highly proliferating white poplar (Populus alba L.) cell suspension cultures. After preliminary screening, four saponins with different structural features in terms of aglycone moieties and sugar chains (saponin 3, a bidesmoside of hederagenin; saponins 4 and 5, monodesmoside and bidesmoside of medicagenic acid respectively, and saponin 10, a bidesmoside of zanhic acid) and different cytotoxicity were selected and used for further investigation on their structure-activity relationship. Transmission Electron Microscopy (TEM) analyses provided for the first time evidence of the effects exerted by saponins on plant cell wall integrity. Exposure to saponin 3 and saponin 10 resulted into disorganization of the outer wall layer and the effect was even more pronounced in white poplar cells treated with the two medicagenic acid derivatives, saponins 4 and 5. Oxidative burst and nitric oxide accumulation were common hallmarks of the response of white poplar cells to saponins. When DNA damage accumulation and DNA repair profiles were evaluated by Single Cell Gel Electrophoresis, induction of single and double strand breaks followed by effective repair was observed within 24h. The reported data are discussed in view of the current issues dealing with saponin structure-activity relationship. Copyright © 2015 Elsevier Ltd. All rights reserved.

  13. Eduard Strasburger (1844-1912): founder of modern plant cell biology.

    Science.gov (United States)

    Volkmann, Dieter; Baluška, František; Menzel, Diedrik

    2012-10-01

    Eduard Strasburger, director of the Botany Institute and the Botanical Garden at the University of Bonn from 1881 to 1912, was one of the most admirable scientists in the field of plant biology, not just as the founder of modern plant cell biology but in addition as an excellent teacher who strongly believed in "education through science." He contributed to plant cell biology by discovering the discrete stages of karyokinesis and cytokinesis in algae and higher plants, describing cytoplasmic streaming in different systems, and reporting on the growth of the pollen tube into the embryo sac and guidance of the tube by synergides. Strasburger raised many problems which are hot spots in recent plant cell biology, e.g., structure and function of the plasmodesmata in relation to phloem loading (Strasburger cells) and signaling, mechanisms of cell plate formation, vesicle trafficking as a basis for most important developmental processes, and signaling related to fertilization.

  14. Plant cell walls throughout evolution: towards a molecular understanding of their design principles.

    Science.gov (United States)

    Sarkar, Purbasha; Bosneaga, Elena; Auer, Manfred

    2009-01-01

    Throughout their life, plants typically remain in one location utilizing sunlight for the synthesis of carbohydrates, which serve as their sole source of energy as well as building blocks of a protective extracellular matrix, called the cell wall. During the course of evolution, plants have repeatedly adapted to their respective niche, which is reflected in the changes of their body plan and the specific design of cell walls. Cell walls not only changed throughout evolution but also are constantly remodelled and reconstructed during the development of an individual plant, and in response to environmental stress or pathogen attacks. Carbohydrate-rich cell walls display complex designs, which together with the presence of phenolic polymers constitutes a barrier for microbes, fungi, and animals. Throughout evolution microbes have co-evolved strategies for efficient breakdown of cell walls. Our current understanding of cell walls and their evolutionary changes are limited as our knowledge is mainly derived from biochemical and genetic studies, complemented by a few targeted yet very informative imaging studies. Comprehensive plant cell wall models will aid in the re-design of plant cell walls for the purpose of commercially viable lignocellulosic biofuel production as well as for the timber, textile, and paper industries. Such knowledge will also be of great interest in the context of agriculture and to plant biologists in general. It is expected that detailed plant cell wall models will require integrated correlative multimodal, multiscale imaging and modelling approaches, which are currently underway.

  15. Plant cell walls throughout evolution: towards a molecular understanding of their design principles

    Energy Technology Data Exchange (ETDEWEB)

    Sarkar, Purbasha; Bosneaga, Elena; Auer, Manfred

    2009-02-16

    Throughout their life, plants typically remain in one location utilizing sunlight for the synthesis of carbohydrates, which serve as their sole source of energy as well as building blocks of a protective extracellular matrix, called the cell wall. During the course of evolution, plants have repeatedly adapted to their respective niche,which is reflected in the changes of their body plan and the specific design of cell walls. Cell walls not only changed throughout evolution but also are constantly remodelled and reconstructed during the development of an individual plant, and in response to environmental stress or pathogen attacks. Carbohydrate-rich cell walls display complex designs, which together with the presence of phenolic polymers constitutes a barrier for microbes, fungi, and animals. Throughout evolution microbes have co-evolved strategies for efficient breakdown of cell walls. Our current understanding of cell walls and their evolutionary changes are limited as our knowledge is mainly derived from biochemical and genetic studies, complemented by a few targeted yet very informative imaging studies. Comprehensive plant cell wall models will aid in the re-design of plant cell walls for the purpose of commercially viable lignocellulosic biofuel production as well as for the timber, textile, and paper industries. Such knowledge will also be of great interest in the context of agriculture and to plant biologists in general. It is expected that detailed plant cell wall models will require integrated correlative multimodal, multiscale imaging and modelling approaches, which are currently underway.

  16. The Complex Cell Wall Composition of Syncytia Induced by Plant Parasitic Cyst Nematodes Reflects Both Function and Host Plant.

    Science.gov (United States)

    Zhang, Li; Lilley, Catherine J; Imren, Mustafa; Knox, J Paul; Urwin, Peter E

    2017-01-01

    Plant-parasitic cyst nematodes induce the formation of specialized feeding structures, syncytia, within their host roots. These unique plant organs serve as the sole nutrient resource for development and reproduction throughout the biotrophic interaction. The multinucleate syncytium, which arises through local dissolution of cell walls and protoplast fusion of multiple adjacent cells, has dense cytoplasm containing numerous organelles, surrounded by thickened outer cell walls that must withstand high turgor pressure. However, little is known about how the constituents of the syncytial cell wall and their conformation support its role during nematode parasitism. We used a set of monoclonal antibodies, targeted to a range of plant cell wall components, to reveal the microstructures of syncytial cell walls induced by four of the most economically important cyst nematode species, Globodera pallida , Heterodera glycines , Heterodera avenae and Heterodera filipjevi , in their respective potato, soybean, and spring wheat host roots. In situ fluorescence analysis revealed highly similar cell wall composition of syncytia induced by G. pallida and H. glycines . Both consisted of abundant xyloglucan, methyl-esterified homogalacturonan and pectic arabinan. In contrast, the walls of syncytia induced in wheat roots by H. avenae and H. filipjevi contain little xyloglucan but are rich in feruloylated xylan and arabinan residues, with variable levels of mixed-linkage glucan. The overall chemical composition of syncytial cell walls reflected the general features of root cell walls of the different host plants. We relate specific components of syncytial cell walls, such as abundant arabinan, methyl-esterification status of pectic homogalacturonan and feruloylation of xylan, to their potential roles in forming a network to support both the strength and flexibility required for syncytium function.

  17. Cyanobacteria as Cell Factories to Produce Plant Secondary Metabolites

    OpenAIRE

    Xue, Yong; He, Qingfang

    2015-01-01

    Cyanobacteria represent a promising platform for the production of plant secondary metabolites. Their capacity to express plant P450 proteins, which have essential functions in the biosynthesis of many plant secondary metabolites, makes cyanobacteria ideal for this purpose, and their photosynthetic capability allows cyanobacteria to grow with simple nutrient inputs. This review summarizes the advantages of using cyanobacteria to transgenically produce plant secondary metabolites. Some techniq...

  18. Monitoring programmed cell death of living plant tissues in microfluidics using electrochemical and optical techniques

    DEFF Research Database (Denmark)

    Mark, Christina; Heiskanen, Arto; Svensson, Birte

    Programmed cell death (PCD) in plants can influence the outcome of yield and quality of crops through its important role in seed germination and the defence process against pathogens. The main scope of the project is to apply microfluidic cell culture for the measurement of electrochemically......, since it is known that reactive oxygen species, which are affected by changes in the redox activity of the cells3, are involved in PCD in plants, but the relationship between and mechanisms behind ROS and PCD is only poorly understood in plant cells4. Recently, it has been shown, using optical detection...

  19. Oxygen transfer rate identifies priming compounds in parsley cells.

    Science.gov (United States)

    Schilling, Jana Viola; Schillheim, Britta; Mahr, Stefan; Reufer, Yannik; Sanjoyo, Sandi; Conrath, Uwe; Büchs, Jochen

    2015-11-25

    secretion as evaluated by fluorescence spectroscopy. RAMOS noninvasively determines the OTR as a measure of the metabolic activity of plant cells. Chemical enhancement of oxygen consumption by salicylic derivatives in parsley cell suspension cultures correlates with the induction of the primed state of enhanced defense that enhances the quantity of Pep13-induced furanocoumarin phytoalexins. Treatment with the priming-active compounds methyl jasmonate and pyraclostrobin also resulted in an enhanced respiration activity. Thus, RAMOS is a novel technology for identifying priming-inducing compounds for agriculture.

  20. Mechanics of Cellulose Synthase Complexes in Living Plant Cells

    Science.gov (United States)

    Zehfroosh, Nina; Liu, Derui; Ramos, Kieran P.; Yang, Xiaoli; Goldner, Lori S.; Baskin, Tobias I.

    The polymer cellulose is one of the major components of the world's biomass with unique and fascinating characteristics such as its high tensile strength, renewability, biodegradability, and biocompatibility. Because of these distinctive aspects, cellulose has been the subject of enormous scientific and industrial interest, yet there are still fundamental open questions about cellulose biosynthesis. Cellulose is synthesized by a complex of transmembrane proteins called ``Cellulose Synthase A'' (CESA) in the plasma membrane. Studying the dynamics and kinematics of the CESA complex will help reveal the mechanism of cellulose synthesis and permit the development and validation of models of CESA motility. To understand what drives these complexes through the cell membrane, we used total internal reflection fluorescence microscopy (TIRFM) and variable angle epi-fluorescence microscopy to track individual, fluorescently-labeled CESA complexes as they move in the hypocotyl and root of living plants. A mean square displacement analysis will be applied to distinguish ballistic, diffusional, and other forms of motion. We report on the results of these tracking experiments. This work was funded by NSF/PHY-1205989.

  1. Cell-specific expression of plant nutrient transporter genes in orchid mycorrhizae.

    Science.gov (United States)

    Fochi, Valeria; Falla, Nicole; Girlanda, Mariangela; Perotto, Silvia; Balestrini, Raffaella

    2017-10-01

    Orchid mycorrhizal protocorms and roots are heterogeneous structures composed of different plant cell-types, where cells colonized by intracellular fungal coils (the pelotons) are close to non-colonized plant cells. Moreover, the fungal coils undergo rapid turnover inside the colonized cells, so that plant cells containing coils at different developmental stages can be observed in the same tissue section. Here, we have investigated by laser microdissection (LMD) the localization of specific plant gene transcripts in different cell-type populations collected from mycorrhizal protocorms and roots of the Mediterranean orchid Serapias vomeracea colonized by Tulasnella calospora. RNAs extracted from the different cell-type populations have been used to study plant gene expression, focusing on genes potentially involved in N uptake and transport and previously identified as up-regulated in symbiotic protocorms. Results clearly showed that some plant N transporters are differentially expressed in cells containing fungal coils at different developmental stages, as well as in non-colonized cells, and allowed the identification of new functional markers associated to coil-containing cells. Copyright © 2017 Elsevier B.V. All rights reserved.

  2. Esau's Plant anatomy: meristems, cells, and tissues of the plant body : their structure, function, and development

    National Research Council Canada - National Science Library

    Evert, Ray Franklin; Esau, Katherine; Eichhorn, Susan E

    2006-01-01

    ... . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . The Body of a Vascular Plant Is Composed of Three Tissue Systems . . . . . . . . . . . . . . . . . . . . . Structurally Stem, Leaf, and Root Differ Primarily...

  3. Application of the comet assay in studies of programmed cell death (PCD in plants

    Directory of Open Access Journals (Sweden)

    Maria Charzyńska

    2014-01-01

    Full Text Available Programmed cell death (PCD in plants is an intensively investigated process. One of the main characteristics of PCD in both animal and plant organisms is the non-random, internucleosomal fragmentation of nuclear DNA, usually analysed using total DNA gel electrophoresis or TUNEL method. In this paper we present application of the "comet assay" (Single Cell Gel Electrophoresis for detection of nDNA degradation in studies of PCD during plant life cycle. We analyzed three types of tissue: anther tapetum, endosperm and mesophyll which were prepared in different ways to obtain a suspension of viable cells (without cell walls. The comet assay gives a possibility of examination of the nDNA degradation in individual cell. This method is significant for studies of the plant tissue differentiation and senescence especially in the cases when it is not possible to isolate large number of cells at the same developmental stage.

  4. Meristem Plant Cells as a Sustainable Source of Redox Actives for Skin Rejuvenation

    Science.gov (United States)

    Korkina, Liudmila G.; Mayer, Wolfgang; de Luca, Chiara

    2017-01-01

    Recently, aggressive advertisement claimed a “magic role” for plant stem cells in human skin rejuvenation. This review aims to shed light on the scientific background suggesting feasibility of using plant cells as a basis of anti-age cosmetics. When meristem cell cultures obtained from medicinal plants are exposed to appropriate elicitors/stressors (ultraviolet, ultrasound ultraviolet (UV), ultrasonic waves, microbial/insect metabolites, heavy metals, organic toxins, nutrient deprivation, etc.), a protective/adaptive response initiates the biosynthesis of secondary metabolites. Highly bioavailable and biocompatible to human cells, low-molecular weight plant secondary metabolites share structural/functional similarities with human non-protein regulatory hormones, neurotransmitters, pigments, polyamines, amino-/fatty acids. Their redox-regulated biosynthesis triggers in turn plant cell antioxidant and detoxification molecular mechanisms resembling human cell pathways. Easily isolated in relatively large quantities from contaminant-free cell cultures, plant metabolites target skin ageing mechanisms, above all redox imbalance. Perfect modulators of cutaneous oxidative state via direct/indirect antioxidant action, free radical scavenging, UV protection, and transition-metal chelation, they are ideal candidates to restore photochemical/redox/immune/metabolic barriers, gradually deteriorating in the ageing skin. The industrial production of plant meristem cell metabolites is toxicologically and ecologically sustainable for fully “biological” anti-age cosmetics. PMID:28498360

  5. Plant cell walls throughout evolution: towards a molecular understanding of their design principles

    OpenAIRE

    Sarkar, Purbasha

    2009-01-01

    Throughout their life, plants typically remain in one location utilizing sunlight for the synthesis of carbohydrates, which serve as their sole source of energy as well as building blocks of a protective extracellular matrix, called the cell wall. During the course of evolution, plants have repeatedly adapted to their respective niche,which is reflected in the changes of their body plan and the specific design of cell walls. Cell walls not only changed throughout evolution but also are consta...

  6. Cysteine-rich peptides (CRPs) mediate diverse aspects of cell-cell communication in plant reproduction and development.

    Science.gov (United States)

    Marshall, Eleanor; Costa, Liliana M; Gutierrez-Marcos, Jose

    2011-03-01

    Cell-cell communication in plants is essential for the correct co-ordination of reproduction, growth, and development. Studies to dissect this mode of communication have previously focussed primarily on the action of plant hormones as mediators of intercellular signalling. In animals, peptide signalling is a well-documented intercellular communication system, however, relatively little is known about this system in plants. In recent years, numerous reports have emerged about small, secreted peptides controlling different aspects of plant reproduction. Interestingly, most of these peptides are cysteine-rich, and there is convincing evidence suggesting multiple roles for related cysteine-rich peptides (CRPs) as signalling factors in developmental patterning as well as during plant pathogen responses and symbiosis. In this review, we discuss how CRPs are emerging as key signalling factors in regulating multiple aspects of vegetative growth and reproductive development in plants.

  7. Immunocytochemical characterization of the cell walls of bean cell suspensions during habituation and dehabituation to dichlobenil

    DEFF Research Database (Denmark)

    Garcia-Angulo, P.; Willats, W. G. T.; Encina, A. E.

    2006-01-01

    The effects of the cellulose inhibitor dichlobenil on the cell wall composition and structure during the habituation/dehabituation process of suspension-cultured bean cells were assessed. A range of techniques were used including cell wall fractionation, sugar analysis, immunofluorescence...... and fluorochrome labelling of resin-embedded sections, and immunodot assays (IDAs) of cell wall fractions. The cell walls from bean cell suspensions with initial levels of habituation to dichlobenil had decreased levels of cellulose, but this effect lessened with increasing numbers of subcultures. All cell walls...

  8. Application of plant cell and tissue culture for the production of phytochemicals in medicinal plants.

    Science.gov (United States)

    Pant, Bijaya

    2014-01-01

    Approximately 80% of the world inhabitants depend on the medicinal plants in the form of traditional formulations for their primary health care system well as in the treatment of a number of diseases since the ancient time. Many commercially used drugs have come from the information of indigenous knowledge of plants and their folk uses. Linking of the indigenous knowledge of medicinal plants to modern research activities provides a new reliable approach, for the discovery of novel drugs much more effectively than with random collection. Increase in population and increasing demand of plant products along with illegal trade are causing depletion of medicinal plants and many are threatened in natural habitat. Plant tissue culture technique has proved potential alternative for the production of desirable bioactive components from plants, to produce the enough amounts of plant material that is needed and for the conservation of threatened species. Different plant tissue culture systems have been extensively studied to improve and enhance the production of plant chemicals in various medicinal plants.

  9. Biotechnological production of pharmaceuticals and biopharmaceuticals in plant cell and organ cultures.

    Science.gov (United States)

    Hidalgo, Diego; Sanchez, Raul; Lalaleo, Liliana; Bonfill, Mercedes; Corchete, Purificacion; Palazon, Javier

    2018-03-09

    Plant biofactories are biotechnological platforms based on plant cell and organ cultures used for the production of pharmaceuticals and biopharmaceuticals, although to date only a few of these systems have successfully been implemented at an industrial level. Metabolic engineering is possibly the most straightforward strategy to boost pharmaceutical production in plant biofactories, but social opposition to the use of GMOs means empirical approaches are still being used. Plant secondary metabolism involves thousands of different enzymes, some of which catalyze specific reactions, giving one product from a particular substrate, whereas others can yield multiple products from the same substrate. This trait opens plant cell biofactories to new applications, in which the natural metabolic machinery of plants can be harnessed for the bioconversion of phytochemicals or even the production of new bioactive compounds. Synthetic biological pipelines involving the bioconversion of natural substrates into products with a high market value may be established by the heterologous expression of target metabolic genes in model plants. To summarize the state of the art of plant biofactories and their applications for the pipeline production of cosme-, pharma- and biopharmaceuticals. In order to demonstrate the great potential of plant biofactories for multiple applications in the biotechnological production of pharmaceuticals and biopharmaceuticals, this review broadly covers the following: plant biofactories based on cell and hairy root cultures; secondary metabolite production; biotransformation reactions; metabolic engineering tools applied in plant biofactories; and biopharmaceutical production. Copyright© Bentham Science Publishers; For any queries, please email at epub@benthamscience.org.

  10. The Complex Cell Wall Composition of Syncytia Induced by Plant Parasitic Cyst Nematodes Reflects Both Function and Host Plant

    Directory of Open Access Journals (Sweden)

    Li Zhang

    2017-06-01

    Full Text Available Plant–parasitic cyst nematodes induce the formation of specialized feeding structures, syncytia, within their host roots. These unique plant organs serve as the sole nutrient resource for development and reproduction throughout the biotrophic interaction. The multinucleate syncytium, which arises through local dissolution of cell walls and protoplast fusion of multiple adjacent cells, has dense cytoplasm containing numerous organelles, surrounded by thickened outer cell walls that must withstand high turgor pressure. However, little is known about how the constituents of the syncytial cell wall and their conformation support its role during nematode parasitism. We used a set of monoclonal antibodies, targeted to a range of plant cell wall components, to reveal the microstructures of syncytial cell walls induced by four of the most economically important cyst nematode species, Globodera pallida, Heterodera glycines, Heterodera avenae and Heterodera filipjevi, in their respective potato, soybean, and spring wheat host roots. In situ fluorescence analysis revealed highly similar cell wall composition of syncytia induced by G. pallida and H. glycines. Both consisted of abundant xyloglucan, methyl-esterified homogalacturonan and pectic arabinan. In contrast, the walls of syncytia induced in wheat roots by H. avenae and H. filipjevi contain little xyloglucan but are rich in feruloylated xylan and arabinan residues, with variable levels of mixed-linkage glucan. The overall chemical composition of syncytial cell walls reflected the general features of root cell walls of the different host plants. We relate specific components of syncytial cell walls, such as abundant arabinan, methyl-esterification status of pectic homogalacturonan and feruloylation of xylan, to their potential roles in forming a network to support both the strength and flexibility required for syncytium function.

  11. DCD – a novel plant specific domain in proteins involved in development and programmed cell death

    Directory of Open Access Journals (Sweden)

    Doerks Tobias

    2005-07-01

    Full Text Available Abstract Background Recognition of microbial pathogens by plants triggers the hypersensitive reaction, a common form of programmed cell death in plants. These dying cells generate signals that activate the plant immune system and alarm the neighboring cells as well as the whole plant to activate defense responses to limit the spread of the pathogen. The molecular mechanisms behind the hypersensitive reaction are largely unknown except for the recognition process of pathogens. We delineate the NRP-gene in soybean, which is specifically induced during this programmed cell death and contains a novel protein domain, which is commonly found in different plant proteins. Results The sequence analysis of the protein, encoded by the NRP-gene from soybean, led to the identification of a novel domain, which we named DCD, because it is found in plant proteins involved in development and cell death. The domain is shared by several proteins in the Arabidopsis and the rice genomes, which otherwise show a different protein architecture. Biological studies indicate a role of these proteins in phytohormone response, embryo development and programmed cell by pathogens or ozone. Conclusion It is tempting to speculate, that the DCD domain mediates signaling in plant development and programmed cell death and could thus be used to identify interacting proteins to gain further molecular insights into these processes.

  12. Induction and selection of mutants from in vitro cultured plant cells

    Energy Technology Data Exchange (ETDEWEB)

    Lee, Yung Il; Kim, Jae Sung; Shin, In Chul; Lee, Sang Jae [Korea Atomic Energy Research Institute, Taejon (Korea, Republic of)

    1994-07-01

    Mutant cell lines are useful for biochemical, physiological and genetical material for marker in various genetic manipulation experiments and for the direct use in crop plant improvement. Mutant selection may lead to the production of plants showing resistance or tolerance to specific environmental stress, such as solinity, drought, toxed metals, herbicides, pathogens and low temperature. In this review, these included the production of the somatic variation, the selection process itself and stability of the selected characters in cell culture and regenerated plant. Which would seem to be useful for improving plants and securring genetic resources. 45 refs. (Author).

  13. Induction and selection of mutants from in vitro cultured plant cells

    International Nuclear Information System (INIS)

    Lee, Yung Il; Kim, Jae Sung; Shin, In Chul; Lee, Sang Jae

    1994-07-01

    Mutant cell lines are useful for biochemical, physiological and genetical material for marker in various genetic manipulation experiments and for the direct use in crop plant improvement. Mutant selection may lead to the production of plants showing resistance or tolerance to specific environmental stress, such as solinity, drought, toxed metals, herbicides, pathogens and low temperature. In this review, these included the production of the somatic variation, the selection process itself and stability of the selected characters in cell culture and regenerated plant. Which would seem to be useful for improving plants and securring genetic resources. 45 refs. (Author)

  14. Characterization of the head end cells at the West Valley Nuclear Fuel Reprocessing Plant

    International Nuclear Information System (INIS)

    Vance, R.F.

    1986-11-01

    The head-end cells at the West Valley Nuclear Fuel Reprocessing Plant are characterized in this report. These cells consist of the Process Mechanical Cell (PMC) where irradiated nuclear fuel was trimmed of excess hardware and sheared into short segments; and the General Purpose Cell (GPC) where the segments were collected and stored prior to dissolution, and leached hulls were packaged for disposal. Between 1966 and 1972, while Nuclear Fuels Services operated the plant, these cells became highly contaminated with radioactive materials. The purpose of this characterization work was to develop technical information as a basis of decontamination and decommissioning planning and engineering. It was accomplished by performing remote in-cell visual examinations, radiation surveys, and sampling. Supplementary information was obtained from available written records, out-of-cell inspections, and interviews with plant personnel

  15. Cell-autonomous defense, re-organization and trafficking of membranes in plant-microbe interactions.

    Science.gov (United States)

    Dörmann, Peter; Kim, Hyeran; Ott, Thomas; Schulze-Lefert, Paul; Trujillo, Marco; Wewer, Vera; Hückelhoven, Ralph

    2014-12-01

    Plant cells dynamically change their architecture and molecular composition following encounters with beneficial or parasitic microbes, a process referred to as host cell reprogramming. Cell-autonomous defense reactions are typically polarized to the plant cell periphery underneath microbial contact sites, including de novo cell wall biosynthesis. Alternatively, host cell reprogramming converges in the biogenesis of membrane-enveloped compartments for accommodation of beneficial bacteria or invasive infection structures of filamentous microbes. Recent advances have revealed that, in response to microbial encounters, plasma membrane symmetry is broken, membrane tethering and SNARE complexes are recruited, lipid composition changes and plasma membrane-to-cytoskeleton signaling is activated, either for pre-invasive defense or for microbial entry. We provide a critical appraisal on recent studies with a focus on how plant cells re-structure membranes and the associated cytoskeleton in interactions with microbial pathogens, nitrogen-fixing rhizobia and mycorrhiza fungi. © 2014 The Authors. New Phytologist © 2014 New Phytologist Trust.

  16. Navigating the transcriptional roadmap regulating plant secondary cell wall deposition

    Directory of Open Access Journals (Sweden)

    Steven Grant Hussey

    2013-08-01

    Full Text Available The current status of lignocellulosic biomass as an invaluable resource in industry, agriculture and health has spurred increased interest in understanding the transcriptional regulation of secondary cell wall (SCW biosynthesis. The last decade of research has revealed an extensive network of NAC, MYB and other families of transcription factors regulating Arabidopsis SCW biosynthesis, and numerous studies have explored SCW-related transcription factors in other dicots and monocots. Whilst the general structure of the Arabidopsis network has been a topic of several reviews, they have not comprehensively represented the detailed protein-DNA and protein-protein interactions described in the literature, and an understanding of network dynamics and functionality has not yet been achieved for SCW formation. Furthermore the methodologies employed in studies of SCW transcriptional regulation have not received much attention, especially in the case of non-model organisms. In this review, we have reconstructed the most exhaustive literature-based network representations to date of SCW transcriptional regulation in Arabidopsis. We include a manipulable Cytoscape representation of the Arabidopsis SCW transcriptional network to aid in future studies, along with a list of supporting literature for each documented interaction. Amongst other topics, we discuss the various components of the network, its evolutionary conservation in plants, putative modules and dynamic mechanisms that may influence network function, and the approaches that have been employed in network inference. Future research should aim to better understand network function and its response to dynamic perturbations, whilst the development and application of genome-wide approaches such as ChIP-seq and systems genetics are in progress for the study of SCW transcriptional regulation in non-model organisms.

  17. Unleashing the potential of the root hair cell as a single plant cell type model in root systems biology

    Directory of Open Access Journals (Sweden)

    Zhenzhen eQiao

    2013-11-01

    Full Text Available Plant root is an organ composed of multiple cell types with different functions. This multicellular complexity limits our understanding of root biology because –omics studies performed at the level of the entire root reflect the average responses of all cells composing the organ. To overcome this difficulty and allow a more comprehensive understanding of root cell biology, an approach is needed that would focus on one single cell type in the plant root. Because of its biological functions (i.e. uptake of water and various nutrients; primary site of infection by nitrogen-fixing bacteria in legumes, the root hair cell is an attractive single cell model to study root cell response to various stresses and treatments. To fully study their biology, we have recently optimized procedures in obtaining root hair cell samples. We culture the plants using an ultrasound aeroponic system maximizing root hair cell density on the entire root systems and allowing the homogeneous treatment of the root system. We then isolate the root hair cells in liquid nitrogen. Isolated root hair yields could be up to 800 to 1000 mg of plant cells from 60 root systems. Using soybean as a model, the purity of the root hair was assessed by comparing the expression level of genes previously identified as soybean root hair specific between preparations of isolated root hair cells and stripped roots, roots devoid in root hairs. Enlarging our tests to include other plant species, our results support the isolation of large quantities of highly purified root hair cells which is compatible with a systems biology approach.

  18. A novel approach for studying programmed cell death in living plant tissues

    DEFF Research Database (Denmark)

    Mark, Christina

    to traditional approaches. Future applications of this type of setup could be used for other types of plant tissues such as leaves or germinating embryos for studying the effects of e.g. biotic and abiotic stresses or for screening of compounds for biological effects. Due to the ease of use and many......Programmed cell death (PCD) is a highly regulated process in which cells are killed as part of developmental programmes or as defence mechanisms against pathogens, but the process is less well understood in plant cells compared to animal cells. Reactive oxygen species (ROS) are involved in PCD...... in plants, but the relationship between and mechanisms behind ROS and PCDhas not yet been fully elucidated due to the involvement of complex signalling networks. Elucidation of these mechanisms and signalling pathways will allow manipulation of cell death in plants, which could help to improve yield...

  19. Effect of Properties and Turgor Pressure on the Indentation Response of Plant Cells

    DEFF Research Database (Denmark)

    Tvergaard, Viggo; Needleman, Alan

    2018-01-01

    The indentation of plant cells by a conical indenter is modeled. The cell wall is represented as a spherical shell consisting of a relatively stiff thin outer layer and a softer thicker inner layer. The state of the interior of the cell is idealized as a specified turgor pressure. Attention...

  20. Metabolism of monoterpenes in cell cultures of common sage (Salvia officinalis)

    International Nuclear Information System (INIS)

    Falk, K.L.; Gershenzon, J.; Croteau, R.

    1990-01-01

    Leaves of common sage (Salvia officinalis) accumulate monoterpenes in glandular trichomes at levels exceeding 15 milligrams per gram fresh weight at maturity, whereas sage cells in suspension culture did not accumulate detectable levels of monoterpenes ( 14 C]sucrose was also virtually undetectable in this cell culture system. In vitro assay of each of the enzymes required for the sequential conversion of the ubiquitous isoprenoid precursor geranyl pyrophosphate to (+)-camphor (a major monoterpene product of sage) in soluble extracts of the cells revealed the presence of activity sufficient to produce (+)-camphor at a readily detectable level (>0.3 micrograms per gram fresh weight) at the late log phase of growth. Other monoterpene synthetic enzymes were present as well. In vivo measurement of the ability to catabolize (+)-camphor in these cells indicated that degradative capability exceeded biosynthetic capacity by at least 1,000-fold. Therefore, the lack of monoterpene accumulation in undifferentiated sage cultures could be attributed to a low level of biosynthetic activity (relative to the intact plant) coupled to a pronounced capacity for monoterpene catabolism

  1. Plant cell wall sugars: sweeteners for a bio-based economy.

    Science.gov (United States)

    Van de Wouwer, Dorien; Boerjan, Wout; Vanholme, Bartel

    2018-02-12

    Global warming and the consequent climate change is one of the major environmental challenges we are facing today. The driving force behind the rise in temperature is our fossil-based economy, which releases massive amounts of the greenhouse gas carbon dioxide into the atmosphere. In order to reduce greenhouse gas emission, we need to scale down our dependency on fossil resources, implying that we need other sources for energy and chemicals to feed our economy. Here, plants have an important role to play; by means of photosynthesis, plants capture solar energy to split water and fix carbon derived from atmospheric carbon dioxide. A significant fraction of the fixed carbon ends up as polysaccharides in the plant cell wall. Fermentable sugars derived from cell wall polysaccharides form an ideal carbon source for the production of bio-platform molecules. However, a major limiting factor in the use of plant biomass as feedstock for the bio-based economy is the complexity of the plant cell wall and its recalcitrance towards deconstruction. To facilitate the release of fermentable sugars during downstream biomass processing, the composition and structure of the cell wall can be engineered. Different strategies to reduce cell wall recalcitrance will be described in this review. The ultimate goal is to obtain a tailor-made biomass, derived from plants with a cell wall optimized for particular industrial or agricultural applications, without affecting plant growth and development. This article is protected by copyright. All rights reserved.

  2. Ceratopteris richardii (C-fern: A model for investigating adaptive modification of vascular plant cell walls

    Directory of Open Access Journals (Sweden)

    Olivier eLeroux

    2013-09-01

    Full Text Available Plant cell walls are essential for most aspects of plant growth, development, and survival, including cell division, expansive cell growth, cell-cell communication, biomechanical properties, and stress responses. Therefore, characterising cell wall diversity contributes to our overall understanding of plant evolution and development. Recent biochemical analyses, concomitantly with whole genome sequencing of plants located at pivotal points in plant phylogeny, have helped distinguish between homologous characters and those which might be more derived. Most plant lineages now have at least one fully sequenced representative and although genome sequences for fern species are in progress they not yet available this group. Ferns offer key advantages for the study of developmental processes leading to vascularisation and complex organs as well as the specific differences between diploid sporophyte tissues and haploid gametophyte tissues and the interplay between them. Ceratopteris richardii has been well investigated building a body of knowledge which combined with the genomic and biochemical information available for other plants will progress our understanding of wall diversity and its impact on evolution and development.

  3. Functional expression of an ajmaline pathway-specific esterase from Rauvolfia in a novel plant-virus expression system.

    Science.gov (United States)

    Ruppert, Martin; Woll, Jörn; Giritch, Anatoli; Genady, Ezzat; Ma, Xueyan; Stöckigt, Joachim

    2005-11-01

    Acetylajmalan esterase (AAE) plays an essential role in the late stage of ajmaline biosynthesis. Based on the partial peptide sequences of AAE isolated and purified from Rauvolfia cell suspensions, a full-length AAE cDNA clone was isolated. The amino acid sequence of AAE has the highest level of identity of 40% to putative lipases known from the Arabidopsis thaliana genome project. Based on the primary structure AAE is a new member of the GDSL lipase superfamily. The expression in Escherichia coli failed although a wide range of conditions were tested. With a novel virus-based plant expression system, it was possible to express AAE functionally in leaves of Nicotiana benthamiana Domin. An extraordinarily high enzyme activity was detected in the Nicotiana tissue, which exceeded that in Rauvolfia serpentina (L.) Benth. ex Kurz cell suspension cultures about 20-fold. This expression allowed molecular analysis of AAE for the first time and increased the number of functionally expressed alkaloid genes from Rauvolfia now to eight, and the number of ajmaline pathway-specific cDNAs to a total of six.

  4. The Role of Plant Cell Wall Proteins in Response to Salt Stress

    Directory of Open Access Journals (Sweden)

    Lyuben Zagorchev

    2014-01-01

    Full Text Available Contemporary agriculture is facing new challenges with the increasing population and demand for food on Earth and the decrease in crop productivity due to abiotic stresses such as water deficit, high salinity, and extreme fluctuations of temperatures. The knowledge of plant stress responses, though widely extended in recent years, is still unable to provide efficient strategies for improvement of agriculture. The focus of study has been shifted to the plant cell wall as a dynamic and crucial component of the plant cell that could immediately respond to changes in the environment. The investigation of plant cell wall proteins, especially in commercially important monocot crops revealed the high involvement of this compartment in plants stress responses, but there is still much more to be comprehended. The aim of this review is to summarize the available data on this issue and to point out the future areas of interest that should be studied in detail.

  5. The nucleus of differentiated root plant cells: modifications induced by arbuscular mycorrhizal fungi

    Directory of Open Access Journals (Sweden)

    G Lingua

    2009-12-01

    Full Text Available The nuclei of plant cells show marked differences in chromatin organisation, related to their DNA content, which ranges from the type with large strands of condensed chromatin (reticulate or chromonematic nuclei to one with mostly decondensed chromatin (chromocentric or diffuse nuclei. A loosening of the chromatin structure generally occurs in actively metabolising cells, such as differentiating and secretory cells, in relation to their high transcriptional activity. Endoreduplication may occur, especially in plants with a small genome, which increases the availability of nuclear templates, the synthesis of DNA, and probably regulates gene expression. Here we describe structural and quantitative changes of the chromatin and their relationship with transcription that occur in differentiated cells following an increase of their metabolism. The nuclei of root cortical cells of three plants with different 2C DNA content (Allium porrum, Pisum sativum and Lycopersicon esculentm and their modifications induced by arbuscular mycorrhization, which strongly increase the metabolic activity of colonised cells, are taken as examples.

  6. Navigating the plant cell: intracellular transport logistics in the green kingdom.

    Science.gov (United States)

    Geitmann, Anja; Nebenführ, Andreas

    2015-10-01

    Intracellular transport in plant cells occurs on microtubular and actin arrays. Cytoplasmic streaming, the rapid motion of plant cell organelles, is mostly driven by an actin-myosin mechanism, whereas specialized functions, such as the transport of large cargo or the assembly of a new cell wall during cell division, are performed by the microtubules. Different modes of transport are used, fast and slow, to either haul cargo over long distances or ascertain high-precision targeting, respectively. Various forms of the actin-specific motor protein myosin XI exist in plant cells and might be involved in different cellular functions. © 2015 Geitmann and Nebenführ. This article is distributed by The American Society for Cell Biology under license from the author(s). Two months after publication it is available to the public under an Attribution–Noncommercial–Share Alike 3.0 Unported Creative Commons License (http://creativecommons.org/licenses/by-nc-sa/3.0).

  7. Exploring the Role of Cell Wall-Related Genes and Polysaccharides during Plant Development.

    Science.gov (United States)

    Tucker, Matthew R; Lou, Haoyu; Aubert, Matthew K; Wilkinson, Laura G; Little, Alan; Houston, Kelly; Pinto, Sara C; Shirley, Neil J

    2018-05-31

    The majority of organs in plants are not established until after germination, when pluripotent stem cells in the growing apices give rise to daughter cells that proliferate and subsequently differentiate into new tissues and organ primordia. This remarkable capacity is not only restricted to the meristem, since maturing cells in many organs can also rapidly alter their identity depending on the cues they receive. One general feature of plant cell differentiation is a change in cell wall composition at the cell surface. Historically, this has been viewed as a downstream response to primary cues controlling differentiation, but a closer inspection of the wall suggests that it may play a much more active role. Specific polymers within the wall can act as substrates for modifications that impact receptor binding, signal mobility, and cell flexibility. Therefore, far from being a static barrier, the cell wall and its constituent polysaccharides can dictate signal transmission and perception, and directly contribute to a cell's capacity to differentiate. In this review, we re-visit the role of plant cell wall-related genes and polysaccharides during various stages of development, with a particular focus on how changes in cell wall machinery accompany the exit of cells from the stem cell niche.

  8. Comparative interactomics: analysis of arabidopsis 14-3-3 complexes reveals highly conserved 14-3-3 interactions between humans and plants.

    Science.gov (United States)

    Paul, Anna-Lisa; Liu, Li; McClung, Scott; Laughner, Beth; Chen, Sixue; Ferl, Robert J

    2009-04-01

    As a first step in the broad characterization of plant 14-3-3 multiprotein complexes in vivo, stringent and specific antibody affinity purification was used to capture 14-3-3s together with their interacting proteins from extracts of Arabidopsis cell suspension cultures. Approximately 120 proteins were identified as potential in vivo 14-3-3 interacting proteins by mass spectrometry of the recovered complexes. Comparison of the proteins in this data set with the 14-3-3 interacting proteins from a similar study in human embryonic kidney cell cultures revealed eight interacting proteins that likely represent reasonably abundant, fundamental 14-3-3 interaction complexes that are highly conserved across all eukaryotes. The Arabidopsis 14-3-3 interaction data set was also compared to a yeast in vivo 14-3-3 interaction data set. Four 14-3-3 interacting proteins are conserved in yeast, humans, and Arabidopsis. Comparisons of the data sets based on biochemical function revealed many additional similarities in the human and Arabidopsis data sets that represent conserved functional interactions, while also leaving many proteins uniquely identified in either Arabidopsis or human cells. In particular, the Arabidopsis interaction data set is enriched for proteins involved in metabolism.

  9. A synthetic glycan microarray enables epitope mapping of plant cell wall glycan-directed antibodies

    DEFF Research Database (Denmark)

    Ruprecht, Colin; Bartetzko, Max P; Senf, Deborah

    2017-01-01

    In the last three decades, more than 200 monoclonal antibodies have been raised against most classes of plant cell wall polysaccharides by different laboratories world-wide. These antibodies are widely used to identify differences in plant cell wall components in mutants, organ and tissue types......, and developmental stages. Despite their importance and broad use, the precise binding epitope for only a few of these antibodies has been determined. Here, we use a plant glycan microarray equipped with 88 synthetic oligosaccharides to comprehensively map the epitopes of plant cell wall glycan-directed antibodies....... Our results reveal the binding epitopes for 78 arabinogalactan-, rhamnogalacturonan-, xylan-, and xyloglucan-directed antibodies. We demonstrate that, with knowledge of the exact epitopes recognized by individual antibodies, specific glycosyl hydrolases can be implemented into immunological cell wall...

  10. Cell wall assembly and intracellular trafficking in plant cells are directly affected by changes in the magnitude of gravitational acceleration.

    Directory of Open Access Journals (Sweden)

    Youssef Chebli

    Full Text Available Plants are able to sense the magnitude and direction of gravity. This capacity is thought to reside in selected cell types within the plant body that are equipped with specialized organelles called statoliths. However, most plant cells do not possess statoliths, yet they respond to changes in gravitational acceleration. To understand the effect of gravity on the metabolism and cellular functioning of non-specialized plant cells, we investigated a rapidly growing plant cell devoid of known statoliths and without gravitropic behavior, the pollen tube. The effects of hyper-gravity and omnidirectional exposure to gravity on intracellular trafficking and on cell wall assembly were assessed in Camellia pollen tubes, a model system with highly reproducible growth behavior in vitro. Using an epi-fluorescence microscope mounted on the Large Diameter Centrifuge at the European Space Agency, we were able to demonstrate that vesicular trafficking is reduced under hyper-gravity conditions. Immuno-cytochemistry confirmed that both in hyper and omnidirectional gravity conditions, the characteristic spatial profiles of cellulose and callose distribution in the pollen tube wall were altered, in accordance with a dose-dependent effect on pollen tube diameter. Our findings suggest that in response to gravity induced stress, the pollen tube responds by modifying cell wall assembly to compensate for the altered mechanical load. The effect was reversible within few minutes demonstrating that the pollen tube is able to quickly adapt to changing stress conditions.

  11. The plant cell wall integrity maintenance mechanism--a case study of a cell wall plasma membrane signaling network.

    Science.gov (United States)

    Hamann, Thorsten

    2015-04-01

    Some of the most important functions of plant cell walls are protection against biotic/abiotic stress and structural support during growth and development. A prerequisite for plant cell walls to perform these functions is the ability to perceive different types of stimuli in both qualitative and quantitative manners and initiate appropriate responses. The responses in turn involve adaptive changes in cellular and cell wall metabolism leading to modifications in the structures originally required for perception. While our knowledge about the underlying plant mechanisms is limited, results from Saccharomyces cerevisiae suggest the cell wall integrity maintenance mechanism represents an excellent example to illustrate how the molecular mechanisms responsible for stimulus perception, signal transduction and integration can function. Here I will review the available knowledge about the yeast cell wall integrity maintenance system for illustration purposes, summarize the limited knowledge available about the corresponding plant mechanism and discuss the relevance of the plant cell wall integrity maintenance mechanism in biotic stress responses. Copyright © 2014 Elsevier Ltd. All rights reserved.

  12. Imaging the Dynamics of Cell Wall Polymer Deposition in the Unicellular Model Plant, Penium margaritaceum.

    Science.gov (United States)

    Domozych, David; Lietz, Anna; Patten, Molly; Singer, Emily; Tinaz, Berke; Raimundo, Sandra C

    2017-01-01

    The unicellular green alga, Penium margaritaceum, represents a novel and valuable model organism for elucidating cell wall dynamics in plants. This organism's cell wall contains several polymers that are highly similar to those found in the primary cell walls of land plants. Penium is easily grown in laboratory culture and is effectively manipulated in various experimental protocols including microplate assays and correlative microscopy. Most importantly, Penium can be live labeled with cell wall-specific antibodies or other probes and returned to culture where specific cell wall developmental events can be monitored. Additionally, live cells can be rapidly cryo-fixed and cell wall surface microarchitecture can be observed with variable pressure scanning electron microscopy. Here, we describe the methodology for maintaining Penium for experimental cell wall enzyme studies.

  13. Redefining plant systems biology: from cell to ecosystem

    NARCIS (Netherlands)

    Keurentjes, J.J.B.; Angenent, G.C.; Dicke, M.; Martins Dos Santos, V.A.P.; Molenaar, J.; Van der Putten, W.H.; de Ruiter, P.C.; Struik, P.C.; Thomma, B.P.H.J.

    2011-01-01

    Molecular biologists typically restrict systems biology to cellular levels. By contrast, ecologists define biological systems as communities of interacting individuals at different trophic levels that process energy, nutrient and information flows. Modern plant breeding needs to increase

  14. Arabinose-rich polymers as an evolutionary strategy to plasticize resurrection plant cell walls against desiccation

    DEFF Research Database (Denmark)

    Moore, John P.; Nguema-Ona, Eric E.; Vicré-Gibouin, Mäite

    2013-01-01

    A variety of Southern African resurrection plants were surveyed using high-throughput cell wall profiling tools. Species evaluated were the dicotyledons, Myrothamnus flabellifolia and Craterostigma plantagineum; the monocotyledons, Xerophyta viscosa, Xerophyta schlecterii, Xerophyta humilis and t......-arabinans, arabinogalactan proteins and arabinoxylans) as the major contributors in ensuring flexibility is maintained and rehydration is facilitated in these plants....

  15. Bleomycin resistance : a new dominant selectable marker for plant cell transformation

    NARCIS (Netherlands)

    Hille, Jacques; Verheggen, Frank; Roelvink, Peter; Franssen, Henk; Kammen, Ab van; Zabel, Pim

    1986-01-01

    Plant cells are sensitive to the antibiotic bleomycin, a DNA damaging glycopeptide. A bleomycin resistance determinant, located on transposon Tn5 and functional in bacteria, has been cloned in a plant expression vector and introduced into Nicotiana plumbaginifolia using Agrobacterium tumefaciens.

  16. A detection method in living plant cells for rapidly monitoring the response of plants to exogenous lanthanum.

    Science.gov (United States)

    Cheng, Mengzhu; Wang, Lihong; Yang, Qing; Huang, Xiaohua

    2018-08-30

    The pollution of rare earth elements (REEs) in ecosystem is becoming more and more serious, so it is urgent to establish methods for monitoring the pollution of REEs. Monitoring environmental pollution via the response of plants to pollutants has become the most stable and accurate method compared with traditional methods, but scientists still need to find the primary response of plants to pollutants to improve the sensitivity and speed of this method. Based on the facts that the initiation of endocytosis is the primary cellular response of the plant leaf cells to REEs and the detection of endocytosis is complex and expensive, we constructed a detection method in living plant cells for rapidly monitoring the response of plants to exogenous lanthanum [La(III), a representative of REEs] by designing a new immuno-electrochemical method for detecting the content change in extracellular vitronectin-like protein (VN) that are closely related to endocytosis. Results showed that when 30 μM La(III) initiated a small amount of endocytosis, the content of extracellular VN increased by 5.46 times, but the structure and function of plasma membrane were not interfered by La(III); when 80 μM La(III) strongly initiated a large amount of endocytosis, the content of extracellular VN increased by 119 times, meanwhile, the structure and function of plasma membrane were damaged. In summary, the detection method can reflect the response of plants to La(III) via detecting the content change in extracellular VN, which provides an effective and convenient way to monitor the response of plants to exogenous REEs. Copyright © 2018. Published by Elsevier Inc.

  17. Evaluating the role of low-speed centrifugation towards transfecting human peripheral blood mononuclear cell culture

    Directory of Open Access Journals (Sweden)

    M Majumdar

    2014-01-01

    Full Text Available The conventional method of transfection of suspension cells by chemical has proven to be very difficult. We present a new transfection protocol, wherein, low-speed centrifugation of cell culture plates immediately after adding the lipid: DNA complex significantly enhances the transfection efficiency. Peripheral blood mononuclear cells (PBMCs were transfected with BLOCK-iT™ Fluorescent Oligo (scrambled siRNA and lipofectamine complex using conventional and low-speed centrifugation modified transfection protocols. The efficiency of transfection was determined using flowcytometer and cell viability was checked using MTT assay. Incorporation of low-speed centrifugation significantly enhances the transfection efficiency of BLOCK-iT™ in the suspension culture of PBMCs as compared to conventional transfection method (99.8% vs 28.3%; P < 0.0001, even at a low concentration of 40 picomoles without affecting the cell viability. Centrifugation enhanced transfection (CET technique is simple, time-saving and novel application without compromising the cell viability in the context of recently popular RNA interference in suspension cultures of PBMCs. This undemanding modification might be applicable to a wide variety of cell lines and solve crucial problem of researchers working with RNA interference in suspension cultures.

  18. Biotransformation of 2-(4-methoxybenzyl)cyclopentanone by Solanum aviculare and Rheum palmatum plant cells

    Czech Academy of Sciences Publication Activity Database

    Soudek, Petr; Wimmer, Zdeněk; Vaněk, Tomáš

    2014-01-01

    Roč. 12, 3-4 (2014), s. 213-216 ISSN 1459-0255 R&D Projects: GA MŠk LH12162 Institutional support: RVO:61389030 Keywords : Solanum aviculare * Rheum palmatum * plant cell culture Subject RIV: DN - Health Impact of the Environment Quality Impact factor: 0.435, year: 2012 http://world-food.net/ biotransformation -of-2-4-methoxybenzylcyclopentanone-by-solanum-aviculare-and-rheum-palmatum-plant-cells/

  19. Microbial community structure elucidates performance of Glyceria maxima plant microbial fuel cell

    OpenAIRE

    Timmers, R.A.; Rothballer, M.; Strik, D.P.B.T.B.; Engel, M.; Schulz, M.; Hartmann, A.; Hamelers, H.V.M.; Buisman, C.J.N.

    2012-01-01

    The plant microbial fuel cell (PMFC) is a technology in which living plant roots provide electron donor, via rhizodeposition, to a mixed microbial community to generate electricity in a microbial fuel cell. Analysis and localisation of the microbial community is necessary for gaining insight into the competition for electron donor in a PMFC. This paper characterises the anode-rhizosphere bacterial community of a Glyceria maxima (reed mannagrass) PMFC. Electrochemically active bacteria (EAB) w...

  20. Microbial community structure elucidates performance of Glyceria maxima plant microbial fuel cell

    OpenAIRE

    Timmers, Ruud A.; Rothballer, Michael; Strik, David P. B. T. B.; Engel, Marion; Schulz, Stephan; Schloter, Michael; Hartmann, Anton; Hamelers, Bert; Buisman, Cees

    2012-01-01

    The plant microbial fuel cell (PMFC) is a technology in which living plant roots provide electron donor, via rhizodeposition, to a mixed microbial community to generate electricity in a microbial fuel cell. Analysis and localisation of the microbial community is necessary for gaining insight into the competition for electron donor in a PMFC. This paper characterises the anode–rhizosphere bacterial community of a Glyceria maxima (reed mannagrass) PMFC. Electrochemically active bacteria (EAB) w...

  1. Extracellular Trapping of Soil Contaminants by Root Border Cells: New Insights into Plant Defense

    Directory of Open Access Journals (Sweden)

    Martha C. Hawes

    2016-01-01

    Full Text Available Soil and water pollution by metals and other toxic chemicals is difficult to measure and control, and, as such, presents an ongoing global threat to sustainable agriculture and human health. Efforts to remove contaminants by plant-mediated pathways, or “phytoremediation”, though widely studied, have failed to yield consistent, predictable removal of biological and chemical contaminants. Emerging research has revealed that one major limitation to using plants to clean up the environment is that plants are programmed to protect themselves: Like white blood cells in animals, border cells released from plant root tips carry out an extracellular trapping process to neutralize threats and prevent injury to the host. Variability in border cell trapping has been found to be correlated with variation in sensitivity of roots to aluminum, and removal of border cell results in increased Al uptake into the root tip. Studies now have implicated border cells in responses of diverse plant roots to a range of heavy metals, including arsenic, copper, cadmium, lead, mercury, iron, and zinc. A better understanding of border cell extracellular traps and their role in preventing toxin uptake may facilitate efforts to use plants as a nondestructive approach to neutralize environmental threats.

  2. Wall extensibility: its nature, measurement and relationship to plant cell growth

    Science.gov (United States)

    Cosgrove, D. J.

    1993-01-01

    Expansive growth of plant cells is controlled principally by processes that loosen the wall and enable it to expand irreversibly. The central role of wall relaxation for cell expansion is reviewed. The most common methods for assessing the extension properties of plant cell walls ( wall extensibility') are described, categorized and assessed critically. What emerges are three fundamentally different approaches which test growing cells for their ability (a) to enlarge at different values of turgor, (b) to induce wall relaxation, and (c) to deform elastically or plastically in response to an applied tensile force. Analogous methods with isolated walls are similarly reviewed. The results of these different assays are related to the nature of plant cell growth and pertinent biophysical theory. I argue that the extensibilities' measured by these assays are fundamentally different from one another and that some are more pertinent to growth than others.

  3. A suitable model plant for control of the set fuel cell-DC/DC converter

    Energy Technology Data Exchange (ETDEWEB)

    Andujar, J.M.; Segura, F.; Vasallo, M.J. [Departamento de Ingenieria Electronica, Sistemas Informaticos y Automatica, E.P.S. La Rabida, Universidad de Huelva, Ctra. Huelva - Palos de la Frontera, S/N, 21819 La Rabida - Palos de la Frontera Huelva (Spain)

    2008-04-15

    In this work a state and transfer function model of the set made up of a proton exchange membrane (PEM) fuel cell and a DC/DC converter is developed. The set is modelled as a plant controlled by the converter duty cycle. In addition to allow setting the plant operating point at any point of its characteristic curve (two interesting points are maximum efficiency and maximum power points), this approach also allows the connection of the fuel cell to other energy generation and storage devices, given that, as they all usually share a single DC bus, a thorough control of the interconnected devices is required. First, the state and transfer function models of the fuel cell and the converter are obtained. Then, both models are related in order to achieve the fuel cell+DC/DC converter set (plant) model. The results of the theoretical developments are validated by simulation on a real fuel cell model. (author)

  4. Evidence for land plant cell wall biosynthetic mechanisms in charophyte green algae

    DEFF Research Database (Denmark)

    Mikkelsen, Maria Dalgaard; Harholt, Jesper; Ulvskov, Peter

    2014-01-01

    in CGA is currently unknown, as no genomes are available, so this study sought to give insight into the evolution of the biosynthetic machinery of CGA through an analysis of available transcriptomes. METHODS: Available CGA transcriptomes were mined for cell wall biosynthesis GTs and compared with GTs...... to colonize land. These cell walls provide support and protection, are a source of signalling molecules, and provide developmental cues for cell differentiation and elongation. The cell wall of land plants is a highly complex fibre composite, characterized by cellulose cross-linked by non......-cellulosic polysaccharides, such as xyloglucan, embedded in a matrix of pectic polysaccharides. How the land plant cell wall evolved is currently unknown: early-divergent chlorophyte and prasinophyte algae genomes contain a low number of glycosyl transferases (GTs), while land plants contain hundreds. The number of GTs...

  5. Altered Cell Wall Plasticity Can Restrict Plant Growth under Ammonium Nutrition.

    Science.gov (United States)

    Podgórska, Anna; Burian, Maria; Gieczewska, Katarzyna; Ostaszewska-Bugajska, Monika; Zebrowski, Jacek; Solecka, Danuta; Szal, Bożena

    2017-01-01

    Plants mainly utilize inorganic forms of nitrogen (N), such as nitrate (NO 3 - ) and ammonium (NH 4 + ). However, the composition of the N source is important, because excess of NH 4 + promotes morphological disorders. Plants cultured on NH 4 + as the sole N source exhibit serious growth inhibition, commonly referred to as "ammonium toxicity syndrome." NH 4 + -mediated suppression of growth may be attributable to both repression of cell elongation and reduction of cell division. The precondition for cell enlargement is the expansion of the cell wall, which requires the loosening of the cell wall polymers. Therefore, to understand how NH 4 + nutrition may trigger growth retardation in plants, properties of their cell walls were analyzed. We found that Arabidopsis thaliana using NH 4 + as the sole N source has smaller cells with relatively thicker cell walls. Moreover, cellulose, which is the main load-bearing polysaccharide revealed a denser assembly of microfibrils. Consequently, the leaf blade tissue showed elevated tensile strength and indicated higher cell wall stiffness. These changes might be related to changes in polysaccharide and ion content of cell walls. Further, NH 4 + toxicity was associated with altered activities of cell wall modifying proteins. The lower activity and/or expression of pectin hydrolyzing enzymes and expansins might limit cell wall expansion. Additionally, the higher activity of cell wall peroxidases can lead to higher cross-linking of cell wall polymers. Overall, the NH 4 + -mediated inhibition of growth is related to a more rigid cell wall structure, which limits expansion of cells. The changes in cell wall composition were also indicated by decreased expression of Feronia , a receptor-like kinase involved in the control of cell wall extension.

  6. Purification, cloning, functional expression and characterization of perakine reductase: the first example from the AKR enzyme family, extending the alkaloidal network of the plant Rauvolfia.

    Science.gov (United States)

    Sun, Lianli; Ruppert, Martin; Sheludko, Yuri; Warzecha, Heribert; Zhao, Yu; Stöckigt, Joachim

    2008-07-01

    Perakine reductase (PR) catalyzes an NADPH-dependent step in a side-branch of the 10-step biosynthetic pathway of the alkaloid ajmaline. The enzyme was cloned by a "reverse-genetic" approach from cell suspension cultures of the plant Rauvolfia serpentina (Apocynaceae) and functionally expressed in Escherichia coli as the N-terminal His(6)-tagged protein. PR displays a broad substrate acceptance, converting 16 out of 28 tested compounds with reducible carbonyl function which belong to three substrate groups: benzaldehyde, cinnamic aldehyde derivatives and monoterpenoid indole alkaloids. The enzyme has an extraordinary selectivity in the group of alkaloids. Sequence alignments define PR as a new member of the aldo-keto reductase (AKR) super family, exhibiting the conserved catalytic tetrad Asp52, Tyr57, Lys84, His126. Site-directed mutagenesis of each of these functional residues to an alanine residue results in >97.8% loss of enzyme activity, in compounds of each substrate group. PR represents the first example of the large AKR-family which is involved in the biosynthesis of plant monoterpenoid indole alkaloids. In addition to a new esterase, PR significantly extends the Rauvolfia alkaloid network to the novel group of peraksine alkaloids.

  7. Method for evaluating the potential of 14C labeled plant polyphenols to cross the blood-brain barrier using accelerator mass spectrometry

    International Nuclear Information System (INIS)

    Janle, Elsa M.; Lila, Mary Ann; Grannan, Michael; Wood, Lauren; Higgins, Aine; Yousef, Gad G.; Rogers, Randy B.; Kim, Helen; Jackson, George S.; Weaver, Connie M.

    2010-01-01

    Bioactive compounds in botanicals may be beneficial in preventing age-related neurodegenerative diseases, but for many compounds conventional methods may be inadequate to detect if these compounds cross the blood-brain barrier or to track the pharmacokinetics in the brain. By combining a number of unique technologies it has been possible to utilize the power of AMS to study the pharmacokinetics of bioactive compounds in the brain at very low concentrations. 14 C labeled compounds can be biosynthesized by plant cell suspension cultures co-incubated with radioisotopically-labeled sucrose and isolated and separated into a series of bioactive fractions. To study the pharmacokinetics and tissue distribution of 14 C labeled plant polyphenols, rats were implanted with jugular catheters, subcutaneous ultrafiltration probes and brain microdialysis probes. Labeled fractions were dosed orally. Interstitial fluid (ISF) and brain microdialysate samples were taken in tandem with blood samples. It was often possible to determine 14 C in blood and ISF with a β-counter. However, brain microdialysate samples 14 C levels on the order of 10 7 atoms/sample required AMS technology. The Brain Microdialysate AUC /Serum AUC ranged from .021- to .029, with the higher values for the glycoside fractions. By using AMS in combination with traditional methods, it is possible to study uptake by blood, distribution to ISF and determine the amount of a dose which can reach the brain and follow the pharmacokinetics in the brain.

  8. Purification and characterization of an iron-induced ferritin from soybean (Glycine max) cell suspensions.

    Science.gov (United States)

    Lescure, A M; Massenet, O; Briat, J F

    1990-11-15

    Ferric citrate induces ferritin synthesis and accumulation in soybean (Glycine max) cell suspension cultures [Proudhon, Briat & Lescure (1989) Plant Physiol. 90, 586-590]. This iron-induced ferritin has been purified from cells grown for 72 h in the presence of either 100 microM- or 500 microM-ferric citrate. It has a molecular mass of about 600 kDa and is built up from a 28 kDa subunit which is recognized by antibodies raised against pea (Pisum sativum) seed ferritin and it has the same N-terminal sequence as this latter, except for residue number 3, which is alanine in pea seed ferritin instead of valine in iron-induced soybean cell ferritin. It contains an average of 1800 atoms of iron per molecule whatever the ferric citrate concentration used to induce its synthesis. It is shown that the presence of 100 microM- or 500 microM-ferric citrate in the culture medium leads respectively to an 11- and 28-fold increase in the total intracellular iron concentration and to a 30- and 60-fold increase in the ferritin concentration. However, the percentage of iron stored in the mineral core of ferritin remains constant whatever the ferric citrate concentration used and represents only 5-6% of cellular iron.

  9. Integration of A Solid Oxide Fuel Cell into A 10 MW Gas Turbine Power Plant

    Directory of Open Access Journals (Sweden)

    Denver F. Cheddie

    2010-04-01

    Full Text Available Power generation using gas turbine power plants operating on the Brayton cycle suffers from low efficiencies. In this work, a solid oxide fuel cell (SOFC is proposed for integration into a 10 MW gas turbine power plant, operating at 30% efficiency. The SOFC system utilizes four heat exchangers for heat recovery from both the turbine outlet and the fuel cell outlet to ensure a sufficiently high SOFC temperature. The power output of the hybrid plant is 37 MW at 66.2% efficiency. A thermo-economic model predicts a payback period of less than four years, based on future projected SOFC cost estimates.

  10. High-throughput mapping of cell-wall polymers within and between plants using novel microarrays

    DEFF Research Database (Denmark)

    Moller, Isabel Eva; Sørensen, Iben; Bernal Giraldo, Adriana Jimena

    2007-01-01

    We describe here a methodology that enables the occurrence of cell-wall glycans to be systematically mapped throughout plants in a semi-quantitative high-throughput fashion. The technique (comprehensive microarray polymer profiling, or CoMPP) integrates the sequential extraction of glycans from...... analysis of mutant and wild-type plants, as demonstrated here for the Arabidopsis thaliana mutants fra8, mur1 and mur3. CoMPP was also applied to Physcomitrella patens cell walls and was validated by carbohydrate linkage analysis. These data provide new insights into the structure and functions of plant...

  11. Evaluating the role of low-speed centrifugation towards transfecting human peripheral blood mononuclear cell culture.

    Science.gov (United States)

    Majumdar, M; Ratho, R; Chawla, Y; Singh, M P

    2014-01-01

    The conventional method of transfection of suspension cells by chemical has proven to be very difficult. We present a new transfection protocol, wherein, low-speed centrifugation of cell culture plates immediately after adding the lipid: DNA complex significantly enhances the transfection efficiency. Peripheral blood mononuclear cells (PBMCs) were transfected with BLOCK-iT™ Fluorescent Oligo (scrambled siRNA) and lipofectamine complex using conventional and low-speed centrifugation modified transfection protocols. The efficiency of transfection was determined using flowcytometer and cell viability was checked using MTT assay. Incorporation of low-speed centrifugation significantly enhances the transfection efficiency of BLOCK-iT™ in the suspension culture of PBMCs as compared to conventional transfection method (99.8% vs 28.3%; P Centrifugation enhanced transfection (CET) technique is simple, time-saving and novel application without compromising the cell viability in the context of recently popular RNA interference in suspension cultures of PBMCs. This undemanding modification might be applicable to a wide variety of cell lines and solve crucial problem of researchers working with RNA interference in suspension cultures.

  12. The plant cell wall in the feeding sites of cyst nematodes.

    Science.gov (United States)

    Bohlmann, Holger; Sobczak, Miroslaw

    2014-01-01

    Plant parasitic cyst nematodes (genera Heterodera and Globodera) are serious pests for many crops. They enter the host roots as migratory second stage juveniles (J2) and migrate intracellularly toward the vascular cylinder using their stylet and a set of cell wall degrading enzymes produced in the pharyngeal glands. They select an initial syncytial cell (ISC) within the vascular cylinder or inner cortex layers to induce the formation of a multicellular feeding site called a syncytium, which is the only source of nutrients for the parasite during its entire life. A syncytium can consist of more than hundred cells whose protoplasts are fused together through local cell wall dissolutions. While the nematode produces a cocktail of cell wall degrading and modifying enzymes during migration through the root, the cell wall degradations occurring during syncytium development are due to the plants own cell wall modifying and degrading proteins. The outer syncytial cell wall thickens to withstand the increasing osmotic pressure inside the syncytium. Furthermore, pronounced cell wall ingrowths can be formed on the outer syncytial wall at the interface with xylem vessels. They increase the surface of the symplast-apoplast interface, thus enhancing nutrient uptake into the syncytium. Processes of cell wall degradation, synthesis and modification in the syncytium are facilitated by a variety of plant proteins and enzymes including expansins, glucanases, pectate lyases and cellulose synthases, which are produced inside the syncytium or in cells surrounding the syncytium.

  13. The plant cell wall in the feeding sites of cyst nematodes

    Directory of Open Access Journals (Sweden)

    Holger eBohlmann

    2014-03-01

    Full Text Available Plant parasitic cyst nematodes (genera Heterodera and Globodera are serious pests for many crops. They enter the host roots as migratory second stage juveniles (J2 and migrate intracellularly towards the vascular cylinder using their stylet and a set of cell wall degrading enzymes produced in the pharyngeal glands. They select an initial syncytial cell (ISC within the vascular cylinder or inner cortex layers to induce the formation of a multicellular feeding site called a syncytium, which is the only source of nutrients for the parasite during its entire life. A syncytium can consist of more than hundred cells whose protoplasts are fused together through local cell wall dissolutions. While the nematode produces a cocktail of cell wall degrading and modifying enzymes during migration through the root, the cell wall degradations occurring during syncytium development are due to the plants own cell wall modifying and degrading proteins. The outer syncytial cell wall thickens to withstand the increasing osmotic pressure inside the syncytium. Furthermore, pronounced cell wall ingrowths can be formed on the outer syncytial wall at the interface with xylem vessels. They increase the surface of the symplast-apoplast interface, thus enhancing nutrient uptake into the syncytium. Processes of cell wall degradation, synthesis and modification in the syncytium are facilitated by a variety of plant proteins and enzymes including expansins, glucanases, pectate lyases and cellulose synthases, which are produced inside the syncytium or in cells surrounding the syncytium.

  14. Thermodynamic Investigation of an Integrated Gasification Plant with Solid Oxide Fuel Cell and Steam Cycles

    DEFF Research Database (Denmark)

    Rokni, Masoud

    2012-01-01

    A gasification plant is integrated on the top of a solid oxide fuel cell (SOFC) cycle, while a steam turbine (ST) cycle is used as a bottoming cycle for the SOFC plant. The gasification plant was fueled by woodchips to produce biogas and the SOFC stacks were fired with biogas. The produced gas...... generator (HRSG). The steam cycle was modeled with a simple single pressure level. In addition, a hybrid recuperator was used to recover more energy from the HRSG and send it back to the SOFC cycle. Thus two different configurations were investigated to study the plants characteristic. Such system...

  15. Modification of cellular thermal sensitivity by cell shape

    International Nuclear Information System (INIS)

    Yasui, L.S.; Kaysen, K.L.

    1987-01-01

    Suspension cultured cells have been generally found to be more resistant to thermal cell kill than monolayer cells. The authors found in CHO cells grown in F10 medium that suspension cultured cells were more resistant to heat at temperatures greater than 43 0 . At 43 0 and 41.5 0 , the clonogenicity was equal. The T/sub 0/ for 43 0 , 44 0 and 46 0 was 15, 1.5 and 1.25 min for monolayer and 15, 10 and 3.75 min for suspension cultured cells, respectively. The difference in heat sensitivities was not due to a trypsin effect or duration of culturing time in suspension. Microscopic examination of the cells showed monolayer cells were flattened while suspension cells were rounded and each had a corresponding altered organization of the cytoskeleton. The amount of cell protein per 10/sup 5/ cells as determined by the standard Lowry assay was approximately equal for both groups at 31 μg protein. When cells were labeled with /sup 3/H-leucine, heated (45 0 , 15 min) and then extracted so only a cytoskeletal fraction remained, they found an increase in protein in heated over unheated cells. Additionally, the polypeptide banding pattern differed in heated (45 0 , 15min) monolayer versus suspension cells with the appearance of a band at about 64 kD in monolayer cells but not in suspension cells. These results indicate that cell shape, as determined by the underlying cytoskeletal organization, modifies the cellular response to thermal exposure

  16. Systems and synthetic biology approaches to alter plant cell walls and reduce biomass recalcitrance.

    Science.gov (United States)

    Kalluri, Udaya C; Yin, Hengfu; Yang, Xiaohan; Davison, Brian H

    2014-12-01

    Fine-tuning plant cell wall properties to render plant biomass more amenable to biofuel conversion is a colossal challenge. A deep knowledge of the biosynthesis and regulation of plant cell wall and a high-precision genome engineering toolset are the two essential pillars of efforts to alter plant cell walls and reduce biomass recalcitrance. The past decade has seen a meteoric rise in use of transcriptomics and high-resolution imaging methods resulting in fresh insights into composition, structure, formation and deconstruction of plant cell walls. Subsequent gene manipulation approaches, however, commonly include ubiquitous mis-expression of a single candidate gene in a host that carries an intact copy of the native gene. The challenges posed by pleiotropic and unintended changes resulting from such an approach are moving the field towards synthetic biology approaches. Synthetic biology builds on a systems biology knowledge base and leverages high-precision tools for high-throughput assembly of multigene constructs and pathways, precision genome editing and site-specific gene stacking, silencing and/or removal. Here, we summarize the recent breakthroughs in biosynthesis and remodelling of major secondary cell wall components, assess the impediments in obtaining a systems-level understanding and explore the potential opportunities in leveraging synthetic biology approaches to reduce biomass recalcitrance. Published 2014. This article is a U.S. Government work and is in the public domain in the USA. Plant Biotechnology Journal published by Society for Experimental Biology and The Association of Applied Biologists and John Wiley & Sons Ltd.

  17. Thermodynamic analysis and optimization of IT-SOFC-based integrated coal gasification fuel cell power plants

    NARCIS (Netherlands)

    Romano, M.C.; Campanari, S.; Spallina, V.; Lozza, G.

    2011-01-01

    This work discusses the thermodynamic analysis of integrated gasification fuel cell plants, where a simple cycle gas turbine works in a hybrid cycle with a pressurized intermediate temperature–solid oxide fuel cell (SOFC), integrated with a coal gasification and syngas cleanup island and a bottoming

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

    NARCIS (Netherlands)

    PRINS, RA; KREULEN, DA

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

  19. Regulatory dephosphorylation of CDK at G₂/M in plants: yeast mitotic phosphatase cdc25 induces cytokinin-like effects in transgenic tobacco morphogenesis.

    Science.gov (United States)

    Lipavská, Helena; Masková, Petra; Vojvodová, Petra

    2011-05-01

    During the last three decades, the cell cycle and its control by cyclin-dependent kinases (CDKs) have been extensively studied in eukaryotes. This endeavour has produced an overall picture that basic mechanisms seem to be largely conserved among all eukaryotes. The intricate regulation of CDK activities includes, among others, CDK activation by CDC25 phosphatase at G₂/M. In plants, however, studies of this regulation have lagged behind as a plant Cdc25 homologue or other unrelated phosphatase active at G₂/M have not yet been identified. Failure to identify a plant mitotic CDK activatory phosphatase led to characterization of the effects of alien cdc25 gene expression in plants. Tobacco, expressing the Schizosaccharomyces pombe mitotic activator gene, Spcdc25, exhibited morphological, developmental and biochemical changes when compared with wild type (WT) and, importantly, increased CDK dephosphorylation at G₂/M. Besides changes in leaf shape, internode length and root development, in day-neutral tobacco there was dramatically earlier onset of flowering with a disturbed acropetal floral capacity gradient typical of WT. In vitro, de novo organ formation revealed substantially earlier and more abundant formation of shoot primordia on Spcdc25 tobacco stem segments grown on shoot-inducing media when compared with WT. Moreover, in contrast to WT, stem segments from transgenic plants formed shoots even without application of exogenous growth regulator. Spcdc25-expressing BY-2 cells exhibited a reduced mitotic cell size due to a shortening of the G₂ phase together with high activity of cyclin-dependent kinase, NtCDKB1, in early S-phase, S/G₂ and early M-phase. Spcdc25-expressing tobacco ('Samsun') cell suspension cultures showed a clustered, more circular, cell phenotype compared with chains of elongated WT cells, and increased content of starch and soluble sugars. Taken together, Spcdc25 expression had cytokinin-like effects on the characteristics studied

  20. Staying Tight: Plasmodesmal Membrane Contact Sites and the Control of Cell-to-Cell Connectivity in Plants.

    Science.gov (United States)

    Tilsner, Jens; Nicolas, William; Rosado, Abel; Bayer, Emmanuelle M

    2016-04-29

    Multicellularity differs in plants and animals in that the cytoplasm, plasma membrane, and endomembrane of plants are connected between cells through plasmodesmal pores. Plasmodesmata (PDs) are essential for plant life and serve as conduits for the transport of proteins, small RNAs, hormones, and metabolites during developmental and defense signaling. They are also the only pathways available for viruses to spread within plant hosts. The membrane organization of PDs is unique, characterized by the close apposition of the endoplasmic reticulum and the plasma membrane and spoke-like filamentous structures linking the two membranes, which define PDs as membrane contact sites (MCSs). This specialized membrane arrangement is likely critical for PD function. Here, we review how PDs govern developmental and defensive signaling in plants, compare them with other types of MCSs, and discuss in detail the potential functional significance of the MCS nature of PDs.

  1. Mechanical properties of plant cell walls probed by relaxation spectra

    DEFF Research Database (Denmark)

    Hansen, Steen Laugesen; Ray, Peter Martin; Karlsson, Anders Ola

    2011-01-01

    Relax, that deduces relaxation spectra from appropriate rheological measurements is presented and made accessible through a Web interface. BayesRelax models the cell wall as a continuum of relaxing elements, and the ability of the method to resolve small differences in cell wall mechanical properties is demonstrated......Transformants and mutants with altered cell wall composition are expected to display a biomechanical phenotype due to the structural role of the cell wall. It is often quite difficult, however, to distinguish the mechanical behavior of a mutant's or transformant's cell walls from that of the wild...... type. This may be due to the plant’s ability to compensate for the wall modification or because the biophysical method that is often employed, determination of simple elastic modulus and breakstrength, lacks the resolving power necessary for detecting subtle mechanical phenotypes. Here, we apply...

  2. Plant cells without detectable plastids are generated in the crumpled leaf mutant of Arabidopsis thaliana.

    Science.gov (United States)

    Chen, Yuling; Asano, Tomoya; Fujiwara, Makoto T; Yoshida, Shigeo; Machida, Yasunori; Yoshioka, Yasushi

    2009-05-01

    Plastids are maintained in cells by proliferating prior to cell division and being partitioned to each daughter cell during cell division. It is unclear, however, whether cells without plastids are generated when plastid division is suppressed. The crumpled leaf (crl) mutant of Arabidopsis thaliana is a plastid division mutant that displays severe abnormalities in plastid division and plant development. We show that the crl mutant contains cells lacking detectable plastids; this situation probably results from an unequal partitioning of plastids to each daughter cell. Our results suggest that crl has a partial defect in plastid expansion, which is suggested to be important in the partitioning of plastids to daughter cells when plastid division is suppressed. The absence of cells without detectable plastids in the accumulation and replication of chloroplasts 6 (arc6) mutant, another plastid division mutant of A. thaliana having no significant defects in plant morphology, suggests that the generation of cells without detectable plastids is one of the causes of the developmental abnormalities seen in crl plants. We also demonstrate that plastids with trace or undetectable amounts of chlorophyll are generated from enlarged plastids by a non-binary fission mode of plastid replication in both crl and arc6.

  3. The plant secretory pathway seen through the lens of the cell wall.

    Science.gov (United States)

    van de Meene, A M L; Doblin, M S; Bacic, Antony

    2017-01-01

    Secretion in plant cells is often studied by looking at well-characterised, evolutionarily conserved membrane proteins associated with particular endomembrane compartments. Studies using live cell microscopy and fluorescent proteins have illuminated the highly dynamic nature of trafficking, and electron microscopy studies have resolved the ultrastructure of many compartments. Biochemical and molecular analyses have further informed about the function of particular proteins and endomembrane compartments. In plants, there are over 40 cell types, each with highly specialised functions, and hence potential variations in cell biological processes and cell wall structure. As the primary function of secretion in plant cells is for the biosynthesis of cell wall polysaccharides and apoplastic transport complexes, it follows that utilising our knowledge of cell wall glycosyltransferases (GTs) and their polysaccharide products will inform us about secretion. Indeed, this knowledge has led to novel insights into the secretory pathway, including previously unseen post-TGN secretory compartments. Conversely, our knowledge of trafficking routes of secretion will inform us about polarised and localised deposition of cell walls and their constituent polysaccharides/glycoproteins. In this review, we look at what is known about cell wall biosynthesis and the secretory pathway and how the different approaches can be used in a complementary manner to study secretion and provide novel insights into these processes.

  4. Intracellular signaling by diffusion: can waves of hydrogen peroxide transmit intracellular information in plant cells?

    DEFF Research Database (Denmark)

    Vestergaard, Christian L.; Flyvbjerg, Henrik; Møller, Ian Max

    2012-01-01

    of the physical and biochemical conditions in plant cells. As model system, we use a H(2)O(2) signal originating at the plasma membrane (PM) and spreading through the cytosol. We consider two maximally simple types of signals, isolated pulses and harmonic oscillations. First we consider the basic limits......Amplitude- and frequency-modulated waves of Ca(2+) ions transmit information inside cells. Reactive Oxygen Species (ROS), specifically hydrogen peroxide, have been proposed to have a similar role in plant cells. We consider the feasibility of such an intracellular communication system in view...

  5. Chemical Synthesis of Oligosaccharides related to the Cell Walls of Plants and Algae

    DEFF Research Database (Denmark)

    Kinnaert, Christine; Daugaard, Mathilde; Nami, Faranak

    2017-01-01

    in good quantities and with high purity. This review contains an overview of those plant and algal polysaccharides, which have been elucidated to date. The majority of the content is devoted to detailed summaries of the chemical syntheses of oligosaccharide fragments of cellulose, hemicellulose, pectin......Plant cell walls are composed of an intricate network of polysaccharides and proteins that varies during the developmental stages of the cell. This makes it very challenging to address the functions of individual wall components in cells, especially for highly complex glycans. Fortunately...

  6. Abilities of some higher plants to hydrolyze the acetates of phenols and aromatic-aliphatic alcohols

    Directory of Open Access Journals (Sweden)

    Agnieszka Mironowicz

    2014-01-01

    Full Text Available In the biotransformations carried out under the same conditions, the whole intact plants of Spirodela punctata, Nephrolepis exaltata, Cyrtomium falcatum, Nephrolepis cordifolia and the suspension cultures of Helianthus tuberosus, Daucus carota and Petunia hybrida hydrolyze (partially or totally the ester bonds of the acetates of phenols and aromatic-aliphatic alcohols and also the menthyl acetate. Nevertheless, the methyl esters of aromatic acids, structurally similar to the former substrates, do not undergo hydrolysis. At the same time, the viability of first four plants was observed for different levels of acetate concentration. The method of continuous preparative hydrolysis of the same acetates was worked out in Cyrtomium falcatum culture.

  7. The development of in-cell remote inspection system in Tokai reprocessing plant

    International Nuclear Information System (INIS)

    Ishibashi, Yuzo

    1985-01-01

    In the Tokai fuel reprocessing plant, the containment is triple, i.e. the vessel containing radioactive material, then the concrete cell structure and finally the housing building. The fuel reprocessing plant is now proceeding with the development of an in-cell remote inspection system. The inspection system is for inspection of the cell itself and the equipment etc. in the cell, concerning the integrity. Described are the following: the course taken and problems in development of the remote inspection system; development of the floor rambling type remote inspection equipment and the multiple armed type, both for inspection of in-cell ''drip trays''; in-cell equipment inspection devices in specifications etc.; problems in its future development. (Mori, K.)

  8. Plant GSK3 proteins regulate xylem cell differentiation downstream of TDIF-TDR signalling

    Science.gov (United States)

    Kondo, Yuki; Ito, Tasuku; Nakagami, Hirofumi; Hirakawa, Yuki; Saito, Masato; Tamaki, Takayuki; Shirasu, Ken; Fukuda, Hiroo

    2014-03-01

    During plant radial growth typically seen in trees, procambial and cambial cells act as meristematic cells in the vascular system to self-proliferate and differentiate into xylem cells. These two processes are regulated by a signalling pathway composed of a peptide ligand and its receptor; tracheary element differentiation inhibitory factor (TDIF) and TDIF RECEPTOR (TDR). Here we show that glycogen synthase kinase 3 proteins (GSK3s) are crucial downstream components of the TDIF signalling pathway suppressing xylem differentiation from procambial cells. TDR interacts with GSK3s at the plasma membrane and activates GSK3s in a TDIF-dependent fashion. Consistently, a specific inhibitor of plant GSK3s strongly induces xylem cell differentiation through BRI1-EMS SUPPRESSOR 1 (BES1), a well-known target transcription factor of GSK3s. Our findings provide insight into the regulation of cell fate determination in meristem maintenance.

  9. Fuel Cell Power Plants Renewable and Waste Fuels

    Science.gov (United States)

    2011-01-13

    logo, Direct FuelCell and “DFC” are all registered trademarks (®) of FuelCell Energy, Inc. Applications •On-site self generation of combined heat... of FuelCell Energy, Inc. Fuels Resources for DFC • Natural Gas and LNG • Propane • Biogas (by Anaerobicnaerobic Digestion) - Municipal Waste...FUEL RESOURCES z NATURAL GAS z PROPANE z DFC H2 (50-60%) z ETHANOL zWASTE METHANE z BIOGAS z COAL GAS Diversity of Fuels plus High Efficiency

  10. Ethnomedicinal survey of medicinal plants used in the management of sickle cell disorder in Southern Nigeria.

    Science.gov (United States)

    Amujoyegbe, O O; Idu, M; Agbedahunsi, J M; Erhabor, J O

    2016-06-05

    The present study entails the medicinal plant species used to manage sickle cell disorder in Southern States of Nigeria. The ethnomedicinal information was gathered through multistage approach from three geopolitical zones of Southern Nigeria, which were purposively selected. Semi-structured questionnaires were administered on 500 respondents in 125 locations. The ethnomedicinal data collected were analyzed using quantitative value indices such as fidelity level (percentage) and use value. The information got was cross checked using literature search and other related materials. Five hundred respondents comprising 53.12% females and 46.88% males were observed. It was noted that 26.70% were illiterate while 73.30% had formal education. Seventy-nine percent is traditional healers, 27% herb traders and the other 4% are those who have awareness of sickle cell disease . One hundred and seventy five plant species belonging to 70 families, of which Fabaceae made up 26.76% and Euphorbiaceae 16.90% forming the highest occurrence. It was observed that leaves were the most common plant part used (69.10%) followed by root (15%) and stem bark (14%) in the preparation for sickle cell management. Majority (48.57%) of these plants were harvested from wild with 38.86% being trees. Citrus aurantifolia and Newbouldia laevis had highest use values of 0.69 and 0.64 respectively. Plants with the least use value (0.001) include Abrus canescens, Acacia xanthophloea, Aerva lanata and Axonopus compressus. The result of fidelity level values of the plant species for the management of Sickle Cell Disorder (SCD) revealed that Citrus aurantifolia had the highest value of 70.2% while Angraecum distichum and Axonopus compressus had the lowest Fidelity Level value of 0.18%. The study revealed that people in the studied areas were well grounded in the medicinal plants used to manage sickle cell disease. This study reported for the first time 102 plant species having anti-sickling potentials with

  11. Characterization of nonderivatized plant cell walls using high-resolution solution-state NMR spectroscopy

    Science.gov (United States)

    Daniel J. Yelle; John Ralph; Charles R. Frihart

    2008-01-01

    A recently described plant cell wall dissolution system has been modified to use perdeuterated solvents to allow direct in-NMR-tube dissolution and high-resolution solution-state NMR of the whole cell wall without derivatization. Finely ground cell wall material dissolves in a solvent system containing dimethylsulfoxide-d6 and 1-methylimidazole-d6 in a ratio of 4:1 (v/...

  12. Ultrasound-microbubble mediated cavitation of plant cells: effects on morphology and viability.

    Science.gov (United States)

    Qin, Peng; Xu, Lin; Zhong, Wenjing; Yu, Alfred C H

    2012-06-01

    The interaction between ultrasound pulses and microbubbles is known to generate acoustic cavitation that may puncture biological cells. This work presents new experimental findings on the bioeffects of ultrasound-microbubble mediated cavitation in plant cells with emphasis on direct observations of morphological impact and analysis of viability trends in tobacco BY-2 cells that are widely studied in higher plant physiology. The tobacco cell suspensions were exposed to 1 MHz ultrasound pulses in the presence of 1% v/v microbubbles (10% duty cycle; 1 kHz pulse repetition frequency; 70 mm between probe and cells; 1-min exposure time). Few bioeffects were observed at low peak negative pressures (cavitation presumably occurred. In contrast, at 0.9 MPa peak negative pressure (with more inertial cavitation activities according to our passive cavitation detection results), random pores were found on tobacco cell wall (observed via scanning electron microscopy) and enhanced exogenous uptake into the cytoplasm was evident (noted in our fluorescein isothiocyanate dextran uptake analysis). Also, instant lysis was observed in 23.4% of cells (found using trypan blue staining) and programmed cell death was seen in 23.3% of population after 12 h (determined by terminal deoxynucleotidyl transferase-mediated deoxyuridine triphosphate nick end labeling [TUNEL]). These bioeffects generally correspond in trend with those for mammalian cells. This raises the possibility of developing ultrasound-microbubble mediated cavitation into a targeted gene transfection paradigm for plant cells and, conversely, adopting plant cells as experimental test-beds for sonoporation-based gene therapy in mammalian cells. Copyright © 2012 World Federation for Ultrasound in Medicine & Biology. Published by Elsevier Inc. All rights reserved.

  13. Plant cells in the context of climate change

    Directory of Open Access Journals (Sweden)

    Marcelo Rubens Machado

    2014-02-01

    Full Text Available Global warming and its origins triggered the beginning to considerable discussion in the last century. Studies of climate models presented in multidisciplinary scientific reports suggest that anthropogenic activities, particularly the emission of gases from the greenhouse effect, are greatly responsible for the current climate changes. The increase of carbon dioxide (CO2 atmospheric concentration has been in discussion in the news, scientific meetings and in public policy debates in several countries. Apart from its impact on global warming, the rising atmospheric CO2 has alerted the scientific community to the need to investigate any morpho-physiological alterations in the plants, given their direct influence on photosynthesis. This article aims to discuss cellular aspects related to plant growth, their behavior of cuticular waxes and the responses of the stomatal development arising from the chemical change to the atmosphere, which are the causes of serious concern and discussion.

  14. Extraction of nucleic acids from yeast cells and plant tissues using ethanol as medium for sample preservation and cell disruption.

    Science.gov (United States)

    Linke, Bettina; Schröder, Kersten; Arter, Juliane; Gasperazzo, Tatiana; Woehlecke, Holger; Ehwald, Rudolf

    2010-09-01

    Here we report that dehydrated ethanol is an excellent medium for both in situ preservation of nucleic acids and cell disruption of plant and yeast cells. Cell disruption was strongly facilitated by prior dehydration of the ethanol using dehydrated zeolite. Following removal of ethanol, nucleic acids were extracted from the homogenate pellet using denaturing buffers. The method provided DNA and RNA of high yield and integrity. Whereas cell wall disruption was essential for extraction of DNA and large RNA molecules, smaller molecules such as tRNAs could be selectively extracted from undisrupted, ethanol-treated yeast cells. Our results demonstrate the utility of absolute ethanol for sample fixation, cell membrane and cell wall disruption, as well as preservation of nucleic acids during sample storage.

  15. Mechanistic Framework for Establishment, Maintenance, and Alteration of Cell Polarity in Plants

    Directory of Open Access Journals (Sweden)

    Pankaj Dhonukshe

    2012-01-01

    Full Text Available Cell polarity establishment, maintenance, and alteration are central to the developmental and response programs of nearly all organisms and are often implicated in abnormalities ranging from patterning defects to cancer. By residing at the distinct plasma membrane domains polar cargoes mark the identities of those domains, and execute localized functions. Polar cargoes are recruited to the specialized membrane domains by directional secretion and/or directional endocytic recycling. In plants, auxin efflux carrier PIN proteins display polar localizations in various cell types and play major roles in directional cell-to-cell transport of signaling molecule auxin that is vital for plant patterning and response programs. Recent advanced microscopy studies applied to single cells in intact plants reveal subcellular PIN dynamics. They uncover the PIN polarity generation mechanism and identified important roles of AGC kinases for polar PIN localization. AGC kinase family members PINOID, WAG1, and WAG2, belonging to the AGC-3 subclass predominantly influence the polar localization of PINs. The emerging mechanism for AGC-3 kinases action suggests that kinases phosphorylate PINs mainly at the plasma membrane after initial symmetric PIN secretion for eventual PIN internalization and PIN sorting into distinct ARF-GEF-regulated polar recycling pathways. Thus phosphorylation status directs PIN translocation to different cell sides. Based on these findings a mechanistic framework evolves that suggests existence of cell side-specific recycling pathways in plants and implicates AGC3 kinases for differential PIN recruitment among them for eventual PIN polarity establishment, maintenance, and alteration.

  16. Plant parasitic nematode effectors target host defence and nuclear functions to establish feeding cells

    Directory of Open Access Journals (Sweden)

    Michaël eQuentin

    2013-03-01

    Full Text Available Plant parasitic nematodes are microscopic worms, the most damaging species of which have adopted a sedentary lifestyle within their hosts. These obligate endoparasites have a biotrophic relationship with plants, in which they induce the differentiation of root cells into hypertrophied, multinucleate feeding cells. Effectors synthesised in the oesophageal glands of the nematode are injected into the plant cells via the