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Sample records for arabidopsis renders transgenic

  1. Transgenic Arabidopsis Gene Expression System

    Science.gov (United States)

    Ferl, Robert; Paul, Anna-Lisa

    2009-01-01

    The Transgenic Arabidopsis Gene Expression System (TAGES) investigation is one in a pair of investigations that use the Advanced Biological Research System (ABRS) facility. TAGES uses Arabidopsis thaliana, thale cress, with sensor promoter-reporter gene constructs that render the plants as biomonitors (an organism used to determine the quality of the surrounding environment) of their environment using real-time nondestructive Green Fluorescent Protein (GFP) imagery and traditional postflight analyses.

  2. Overexpression of Arabidopsis AnnAt8 Alleviates Abiotic Stress in Transgenic Arabidopsis and Tobacco

    Science.gov (United States)

    Yadav, Deepanker; Ahmed, Israr; Shukla, Pawan; Boyidi, Prasanna; Kirti, Pulugurtha Bharadwaja

    2016-01-01

    Abiotic stress results in massive loss of crop productivity throughout the world. Because of our limited knowledge of the plant defense mechanisms, it is very difficult to exploit the plant genetic resources for manipulation of traits that could benefit multiple stress tolerance in plants. To achieve this, we need a deeper understanding of the plant gene regulatory mechanisms involved in stress responses. Understanding the roles of different members of plant gene families involved in different stress responses, would be a step in this direction. Arabidopsis, which served as a model system for the plant research, is also the most suitable system for the functional characterization of plant gene families. Annexin family in Arabidopsis also is one gene family which has not been fully explored. Eight annexin genes have been reported in the genome of Arabidopsis thaliana. Expression studies of different Arabidopsis annexins revealed their differential regulation under various abiotic stress conditions. AnnAt8 (At5g12380), a member of this family has been shown to exhibit ~433 and ~175 fold increase in transcript levels under NaCl and dehydration stress respectively. To characterize Annexin8 (AnnAt8) further, we have generated transgenic Arabidopsis and tobacco plants constitutively expressing AnnAt8, which were evaluated under different abiotic stress conditions. AnnAt8 overexpressing transgenic plants exhibited higher seed germination rates, better plant growth, and higher chlorophyll retention when compared to wild type plants under abiotic stress treatments. Under stress conditions transgenic plants showed comparatively higher levels of proline and lower levels of malondialdehyde compared to the wild-type plants. Real-Time PCR analyses revealed that the expression of several stress-regulated genes was altered in AnnAt8 over-expressing transgenic tobacco plants, and the enhanced tolerance exhibited by the transgenic plants can be correlated with altered expressions of

  3. Overexpression of SOS (Salt Overly Sensitive)Genes Increases Salt Tolerance in Transgenic Arabidopsis

    Institute of Scientific and Technical Information of China (English)

    Qing Yang; Zhi-Zhong Chen; Xiao-Feng Zhoua; Hai-Bo Yin; Xia Li; Xiu-Fang Xin; Xu-Hui Hong; Jian-Kang Zhu; Zhizhong Gong

    2009-01-01

    Soil salinity is a major abiotic stress that decreases plant growth and productivity. Recently, it was reported that plants overexpressing AtNHX1 or SOS1 have significantly increased salt tolerance. To test whether overexpression of multiple genes can improve plant salt tolerance even more, we produced six different transgenic Arabidopsis plants that overexpress AtNHX1, SOS3, AtNHXl + SOS3, SOS1, SOS2 + SOS3, or SOS1 + SOS2 + SOS3. Northern blot analyses confirmed the presence of high levels of the relevant gene transcripts in transgenic plants. Transgenic Arabidopsis plants overexpressing AtNHX1 alone did not present any significant increase in salt tolerance, contrary to earlier reports. We found that transgenic plants overexpressing SOS3 exhibit increased salt tolerance similar to plants overexpressing SOS1. Moreover, salt tolerance of transgenic plants overexpressing AtNHXl + SOS3, 50S2 + SOS3, or SOS1 + SOS2 +SOS3, respectively, appeared similar to the tolerance of transgenic plants overexpressing either SOS1 or SOS3 alone.

  4. Transgenic Citrus Expressing an Arabidopsis NPR1 Gene Exhibit Enhanced Resistance against Huanglongbing (HLB; Citrus Greening)

    OpenAIRE

    Dutt, Manjul; Barthe, Gary; Irey, Michael; Grosser, Jude

    2015-01-01

    Commercial sweet orange cultivars lack resistance to Huanglongbing (HLB), a serious phloem limited bacterial disease that is usually fatal. In order to develop sustained disease resistance to HLB, transgenic sweet orange cultivars ‘Hamlin’ and ‘Valencia’ expressing an Arabidopsis thaliana NPR1 gene under the control of a constitutive CaMV 35S promoter or a phloem specific Arabidopsis SUC2 (AtSUC2) promoter were produced. Overexpression of AtNPR1 resulted in trees with normal phenotypes that e...

  5. Arabidopsis DREB1B in transgenic Salvia miltiorrhiza increased tolerance to drought stress without stunting growth.

    Science.gov (United States)

    Wei, Tao; Deng, Kejun; Gao, Yonghong; Liu, Yu; Yang, Meiling; Zhang, Lipeng; Zheng, Xuelian; Wang, Chunguo; Song, Wenqin; Chen, Chengbin; Zhang, Yong

    2016-07-01

    Multiple stress response genes are controlled by transcription factors in a coordinated manner; therefore, these factors can be used for molecular plant breeding. CBF1/DREB1B, a known stress-inducible gene, was isolated from Arabidopsis thaliana and introduced into Salvia miltiorrhiza under the control of the CaMV35S or RD29A promoter. Under drought stress, relative water content, chlorophyll content, and the net photosynthetic rate were observed to be higher in the transgenic lines than in the wild type (WT). Moreover, O2(-) and H2O2 accumulation was observed to be lower in the transgenic lines. Additional analyses revealed that the AtDREB1B transgenic plants generally displayed lesser malondialdehyde (MDA) but higher superoxide dismutase (SOD), catalase (CAT), and peroxidase (POD) activities than the WT under drought stress. Quantitative real-time polymerase chain reaction of a subset of genes involved in photosynthesis, stress response, carbohydrate metabolism, and cell protection further verified that AtDREB1B could enhance tolerance to drought by activating different downstream DREB/CBF genes in the transgenic plants. Furthermore, no growth inhibition was detected in transgenic S. miltiorrhiza plants that expressed AtDREB1B driven by either the constitutive CaMV35S promoter or the stress-inducible RD29A promoter. Together, these results suggest that AtDREB1B is a good candidate gene for increasing drought tolerance in transgenic S. miltiorrhiza. PMID:27002402

  6. AtMYB12 regulates flavonoids accumulation and abiotic stress tolerance in transgenic Arabidopsis thaliana.

    Science.gov (United States)

    Wang, Feibing; Kong, Weili; Wong, Gary; Fu, Lifeng; Peng, Rihe; Li, Zhenjun; Yao, Quanhong

    2016-08-01

    In plants, transcriptional regulation is the most important tool for modulating flavonoid biosynthesis. The AtMYB12 gene from Arabidopsis thaliana has been shown to regulate the expression of key enzyme genes involved in flavonoid biosynthesis, leading to the increased accumulation of flavonoids. In this study, the codon-optimized AtMYB12 gene was chemically synthesized. Subcellular localization analysis in onion epidermal cells indicated that AtMYB12 was localized to the nucleus. Its overexpression significantly increased accumulation of flavonoids and enhanced salt and drought tolerance in transgenic Arabidopsis plants. Real-time quantitative PCR (qRT-PCR) analysis showed that overexpression of AtMYB12 resulted in the up-regulation of genes involved in flavonoid biosynthesis, abscisic acid (ABA) biosynthesis, proline biosynthesis, stress responses and ROS scavenging under salt and drought stresses. Further analyses under salt and drought stresses showed significant increases of ABA, proline content, superoxide dismutase (SOD) and peroxidase (POD) activities, as well as significant reduction of H2O2 and malonaldehyde (MDA) content. The results demonstrate the explicit role of AtMYB12 in conferring salt and drought tolerance by increasing the levels of flavonoids and ABA in transgenic Arabidopsis. The AtMYB12 gene has the potential to be used to enhance tolerance to abiotic stresses in plants. PMID:27033553

  7. Overexpression of Actinidia deliciosa pyruvate decarboxylase 1 gene enhances waterlogging stress in transgenic Arabidopsis thaliana.

    Science.gov (United States)

    Zhang, Ji-Yu; Huang, Sheng-Nan; Wang, Gang; Xuan, Ji-Ping; Guo, Zhong-Ren

    2016-09-01

    Ethanolic fermentation is classically associated with waterlogging tolerance when plant cells switch from respiration to anaerobic fermentation. Pyruvate decarboxylase (PDC), which catalyzes the first step in this pathway, is thought to be the main regulatory enzyme. Here, we cloned a full-length PDC cDNA sequence from kiwifruit, named AdPDC1. We determined the expression of the AdPDC1 gene in kiwifruit under different environmental stresses using qRT-PCR, and the results showed that the increase of AdPDC1 expression during waterlogging stress was much higher than that during salt, cold, heat and drought stresses. Overexpression of kiwifruit AdPDC1 in transgenic Arabidopsis enhanced the resistance to waterlogging stress but could not enhance resistance to cold stress at five weeks old seedlings. Overexpression of kiwifruit AdPDC1 in transgenic Arabidopsis could not enhance resistance to NaCl and mannitol stresses at the stage of seed germination and in early seedlings. These results suggested that the kiwifruit AdPDC1 gene is required during waterlogging but might not be required during other environmental stresses. Expression of the AdPDC1 gene was down-regulated by abscisic acid (ABA) in kiwifruit, and overexpression of the AdPDC1 gene in Arabidopsis inhibited seed germination and root length under ABA treatment, indicating that ABA might negatively regulate the AdPDC1 gene under waterlogging stress. PMID:27191596

  8. DICER-LIKE2 plays a primary role in transitive silencing of transgenes in Arabidopsis.

    Directory of Open Access Journals (Sweden)

    Sizolwenkosi Mlotshwa

    Full Text Available Dicer-like (DCL enzymes play a pivotal role in RNA silencing in plants, processing the long double-stranded RNA (dsRNA that triggers silencing into the primary short interfering RNAs (siRNAs that mediate it. The siRNA population can be augmented and silencing amplified via transitivity, an RNA-dependent RNA polymerase (RDR-dependent pathway that uses the target RNA as substrate to generate secondary siRNAs. Here we report that Arabidopsis DCL2-but not DCL4-is required for transitivity in cell-autonomous, post-transcriptional silencing of transgenes. An insertion mutation in DCL2 blocked sense transgene-induced silencing and eliminated accumulation of the associated RDR-dependent siRNAs. In hairpin transgene-induced silencing, the dcl2 mutation likewise eliminated accumulation of secondary siRNAs and blocked transitive silencing, but did not block silencing mediated by primary siRNAs. Strikingly, in all cases, the dcl2 mutation eliminated accumulation of all secondary siRNAs, including those generated by other DCL enzymes. In contrast, mutations in DCL4 promoted a dramatic shift to transitive silencing in the case of the hairpin transgene and enhanced silencing induced by the sense transgene. Suppression of hairpin and sense transgene silencing by the P1/HC-Pro and P38 viral suppressors was associated with elimination of secondary siRNA accumulation, but the suppressors did not block processing of the stem of the hairpin transcript into primary siRNAs. Thus, these viral suppressors resemble the dcl2 mutation in their effects on siRNA biogenesis. We conclude that DCL2 plays an essential, as opposed to redundant, role in transitive silencing of transgenes and may play a more important role in silencing of viruses than currently thought.

  9. Expression and detection of the FMDV VP1 transgene and expressed structural protein in Arabidopsis thaliana

    OpenAIRE

    Pan, Li; Zhang, Yongguang; Wang, Yonglu; Lv, Jianliang; Zhou, Peng; Zhang, Zhongwang

    2011-01-01

    To explore the feasibility of developing a new type of plantderived foot-and-mouth disease virus (FMDV) oral vaccine, the plant seed-specific expression vector p7SBin438/VP1 carrying the VP1 gene of the FMDV strain O/China/99 was constructed and transformed into Agrobacterium tumefaciens strain GV3101. This strain was used for transformation of Arabidopsis thaliana via the floral-dip method. The kanamycin-resistant transgenic plants were selected, and the VP1 gene and protein expressions were...

  10. Transgenic Citrus Expressing an Arabidopsis NPR1 Gene Exhibit Enhanced Resistance against Huanglongbing (HLB; Citrus Greening.

    Directory of Open Access Journals (Sweden)

    Manjul Dutt

    Full Text Available Commercial sweet orange cultivars lack resistance to Huanglongbing (HLB, a serious phloem limited bacterial disease that is usually fatal. In order to develop sustained disease resistance to HLB, transgenic sweet orange cultivars 'Hamlin' and 'Valencia' expressing an Arabidopsis thaliana NPR1 gene under the control of a constitutive CaMV 35S promoter or a phloem specific Arabidopsis SUC2 (AtSUC2 promoter were produced. Overexpression of AtNPR1 resulted in trees with normal phenotypes that exhibited enhanced resistance to HLB. Phloem specific expression of NPR1 was equally effective for enhancing disease resistance. Transgenic trees exhibited reduced diseased severity and a few lines remained disease-free even after 36 months of planting in a high-disease pressure field site. Expression of the NPR1 gene induced expression of several native genes involved in the plant defense signaling pathways. The AtNPR1 gene being plant derived can serve as a component for the development of an all plant T-DNA derived consumer friendly GM tree.

  11. Transgenic Citrus Expressing an Arabidopsis NPR1 Gene Exhibit Enhanced Resistance against Huanglongbing (HLB; Citrus Greening).

    Science.gov (United States)

    Dutt, Manjul; Barthe, Gary; Irey, Michael; Grosser, Jude

    2015-01-01

    Commercial sweet orange cultivars lack resistance to Huanglongbing (HLB), a serious phloem limited bacterial disease that is usually fatal. In order to develop sustained disease resistance to HLB, transgenic sweet orange cultivars 'Hamlin' and 'Valencia' expressing an Arabidopsis thaliana NPR1 gene under the control of a constitutive CaMV 35S promoter or a phloem specific Arabidopsis SUC2 (AtSUC2) promoter were produced. Overexpression of AtNPR1 resulted in trees with normal phenotypes that exhibited enhanced resistance to HLB. Phloem specific expression of NPR1 was equally effective for enhancing disease resistance. Transgenic trees exhibited reduced diseased severity and a few lines remained disease-free even after 36 months of planting in a high-disease pressure field site. Expression of the NPR1 gene induced expression of several native genes involved in the plant defense signaling pathways. The AtNPR1 gene being plant derived can serve as a component for the development of an all plant T-DNA derived consumer friendly GM tree. PMID:26398891

  12. Specimen block counter-staining for localization of GUS expression in transgenic arabidopsis and tobacco

    Science.gov (United States)

    Kim, M. K.; Choi, J-W; Jeon, J-H; Franceschi, V. R.; Davin, L. B.; Lewis, N. G.

    2002-01-01

    A simple counter-staining procedure has been developed for comparative beta-glucuronidase (GUS) expression and anatomical localization in transgenic herbaceous arabidopsis and tobacco. This protocol provides good anatomical visualization for monitoring chimeric gene expression at both the organ and tissue levels. It can be used with different histochemical stains and can be extended to the study of woody species. The specimens are paraffin-embedded, the block is trimmed to reveal internal structure, safranin-O staining solution is briefly applied to the surface of the block, then washed off and, after drying, a drop of immersion oil is placed on the stained surface for subsequent photographic work. This gives tissue counter-staining with good structural preservation without loss of GUS staining product; moreover, sample observation is rapid and efficient compared to existing procedures.

  13. The Miscanthus NAC transcription factor MlNAC9 enhances abiotic stress tolerance in transgenic Arabidopsis.

    Science.gov (United States)

    Zhao, Xun; Yang, Xuanwen; Pei, Shengqiang; He, Guo; Wang, Xiaoyu; Tang, Qi; Jia, Chunlin; Lu, Ying; Hu, Ruibo; Zhou, Gongke

    2016-07-15

    NAC (NAM, ATAF1/2, and CUC2) transcription factors are known to play important roles in responses to abiotic stresses in plants. Currently, little information regarding the functional roles of NAC genes in stress tolerance is available in Miscanthus lutarioriparius, a promising bioenergy plant for cellulosic ethanol production. In this study, we carried out the functional characterization of MlNAC9 in abiotic stresses. MlNAC9 was shown to act as a nuclear localized transcription activator with the activation domain in its C-terminus. The overexpression of MlNAC9 in Arabidopsis conferred hypersensitivity to abscisic acid (ABA) at seed germination and root elongation stages. In addition, the overexpression of MlNAC9 led to increased seed germination rate and root growth under salt (NaCl) treatment. Meanwhile, the transgenic Arabidopsis overexpressing MlNAC9 showed enhanced tolerance to drought and cold stresses. The expression of stress-responsive marker genes was significantly increased in MlNAC9 overexpression lines compared to that of WT under ABA, drought, salt, and cold stresses. Correspondingly, the activities of antioxidant enzymes superoxide dismutase (SOD), peroxidase (POD), and catalase (CAT) were significantly increased and the malondialdehyde (MDA) content was lower accumulated in MlNAC9 overexpression lines under drought and salt treatments. These results indicated that the overexpression of MlNAC9 improved the tolerance to abiotic stresses via an ABA-dependent pathway, and the enhanced tolerance of transgenic plants was mainly attributed to the increased expression of stress-responsive genes and the enhanced scavenging capability of reactive oxygen species (ROS). PMID:27085481

  14. The sunflower transcription factor HaHB11 improves yield, biomass and tolerance to flooding in transgenic Arabidopsis plants.

    Science.gov (United States)

    Cabello, Julieta V; Giacomelli, Jorge I; Piattoni, Claudia V; Iglesias, Alberto A; Chan, Raquel L

    2016-03-20

    HaHB11 is a member of the sunflower homeodomain-leucine zipper I subfamily of transcription factors. The analysis of a sunflower microarray hybridized with RNA from HaHB11-transformed leaf-disks indicated the regulation of many genes encoding enzymes from glycolisis and fermentative pathways. A 1300bp promoter sequence, fused to the GUS reporter gene, was used to transform Arabidopsis plants showing an induction of expression after flooding treatments, concurrently with HaHB11 regulation by submergence in sunflower. Arabidopsis transgenic plants expressing HaHB11 under the control of the CaMV 35S promoter and its own promoter were obtained and these plants exhibited significant increases in rosette and stem biomass. All the lines produced more seeds than controls and particularly, those of high expression level doubled seeds yield. Transgenic plants also showed tolerance to flooding stress, both to submergence and waterlogging. Carbohydrates contents were higher in the transgenics compared to wild type and decreased less after submergence treatments. Finally, transcript levels of selected genes involved in glycolisis and fermentative pathways as well as the corresponding enzymatic activities were assessed both, in sunflower and transgenic Arabidopsis plants, before and after submergence. Altogether, the present work leads us to propose HaHB11 as a biotechnological tool to improve crops yield, biomass and flooding tolerance. PMID:26876611

  15. Over-expression of an Arabidopsis δ-OAT gene enhances salt and drought tolerance in transgenic rice

    Institute of Scientific and Technical Information of China (English)

    WU Liangqi; FAN Zhanmin; GUO Lei; LI Yongqing; ZHANG Wenjing; QU Li-Jia; CHEN Zhangliang

    2003-01-01

    δ-OAT, ornithine-δ-aminotransferase, is the key enzyme involved in proline biosynthesis. In this study the Arabidopsisδ-OAT gene was transferred into rice (Oryza sativa L. ssp japonica cv. Zhongzuo 321), whose successful integration was demonstrated by PCR and Southern blot analysis. The over-expression of the gene in transgenic rice was also confirmed. Biochemical analysis showed that, under salt or drought stress conditions, proline contents in the leaves and roots in transgenic rice plants were 5- to 15-fold of those in non-transgenic controls. Under stress conditions, germinating rate of transgenic lines is higher than that of controls. Although the growth of rice plants tested were more and more retarded with the increasing of NaCl concentration, the transgenic plants grow faster compared to the controls under the same stress condition. Meanwhile, the resistance to KCl and MgSO4 stresses was also found enhanced in transgenic rice. Furthermore, the over-expression ofδ-OAT also improved the yield of transgenic plants under stress conditions. The average yield per plant of transgenic lines increases about 12%-41% more than that of control lines under 0.1 mol/L NaCl stress. These data indicated that the over-expression of δ-OAT, with the accumulation of proline, resulted in the enhancement of salt and drought tolerance and an increase of rice yield, which is of significance in agriculture.

  16. Phytoremediation of the organic Xenobiotic simazine by p450-1a2 transgenic Arabidopsis thaliana plants.

    Science.gov (United States)

    Azab, Ehab; Hegazy, Ahmad K; El-Sharnouby, Mohamed E; Abd Elsalam, Hassan E

    2016-07-01

    The potential use of human P450-transgenic plants for phytoremediation of pesticide contaminated soils was tested in laboratory and greenhouse experiments. The transgenic P450 CYP1A2 gene Arabidopsis thaliana plants metabolize number of herbicides, insecticides and industrial chemicals. The P450 isozymes CYP1A2 expressed in A. thaliana were examined regarding the herbicide simazine (SIM). Transgenic A. thaliana plants expressing CYP1A2 gene showed significant resistance to SIM supplemented either in plant growth medium or sprayed on foliar parts. The results showed that SIM produces harmful effect on both rosette diameter and primary root length of the wild type (WT) plants. In transgenic A. thaliana lines, the rosette diameter and primary root length were not affected by SIM concentrations used in this experiment. The results indicate that CYP1A2 can be used as a selectable marker for plant transformation, allowing efficient selection of transgenic lines in growth medium and/or in soil-grown plants. The transgenic A. thaliana plants exhibited a healthy growth using doses of up to 250 μmol SIM treatments, while the non-transgenic A. thaliana plants were severely damaged with doses above 50 μmol SIM treatments. The transgenic A. thaliana plants can be used as phytoremediator of environmental SIM contaminants. PMID:26771455

  17. Expression of Arabidopsis Bax Inhibitor-1 in transgenic sugarcane confers drought tolerance.

    Science.gov (United States)

    Ramiro, Daniel Alves; Melotto-Passarin, Danila Montewka; Barbosa, Mariana de Almeida; Santos, Flavio Dos; Gomez, Sergio Gregorio Perez; Massola Júnior, Nelson Sidnei; Lam, Eric; Carrer, Helaine

    2016-09-01

    The sustainability of global crop production is critically dependent on improving tolerance of crop plants to various types of environmental stress. Thus, identification of genes that confer stress tolerance in crops has become a top priority especially in view of expected changes in global climatic patterns. Drought stress is one of the abiotic stresses that can result in dramatic loss of crop productivity. In this work, we show that transgenic expression of a highly conserved cell death suppressor, Bax Inhibitor-1 from Arabidopsis thaliana (AtBI-1), can confer increased tolerance of sugarcane plants to long-term (>20 days) water stress conditions. This robust trait is correlated with an increased tolerance of the transgenic sugarcane plants, especially in the roots, to induction of endoplasmic reticulum (ER) stress by the protein glycosylation inhibitor tunicamycin. Our findings suggest that suppression of ER stress in C4 grasses, which include important crops such as sorghum and maize, can be an effective means of conferring improved tolerance to long-term water deficit. This result could potentially lead to improved resilience and yield of major crops in the world. PMID:26872943

  18. Mechanisms of Salt Tolerance in Transgenic Arabidopsis thaliana Carrying a Peroxisomal Ascorbate Peroxidase Gene from Barley

    Institute of Scientific and Technical Information of China (English)

    XU Wei-Feng; SHI Wei-Ming; A. UEDA; T. TAKABE

    2008-01-01

    Ascorbate peroxidases (APX), localized in the cytosol, peroxisome, mitochondria, and chloroplasts of plant cells,catalyze the reduction of H2O2 to water by using ascorbic acid as the specific electron donor. To determine the role of peroxisomal type ascorbate peroxidasc (pAPX), an antioxidant enzyme, in protection against salt-induced oxidative stress, transgenic Arabidopsis thaliana plant carrying a pAPX gene (HvAPX1) from barley (Hordeum vulgare L.) was analyzed. The transgenic line pAPX3 was found to be more tolerant to salt stress than the wild type. Irrespective of salt stress, there were no significant differences in Na+, K+, Ca2+, and Mg2+ contents and the ratio of K+ to Na+ between pAPX3 and the wild type. Clearly, the salt tolerance in pAPX3 was not due to the maintenance and reestablishment of cellular ion homeostasis. However, the degree of H2O2 and lipid peroxidation (measured as the levels of malondialdehyde)accumulation under salt stress was higher in the wild type than in pAPX3. The mechanism of salt tolerance in transgenic pAPX3 can thus be explained by reduction of oxidative stress injury. Under all conditions tested, activities of superoxide,glutathionc reductase, and catalase were not significantly different between pAPX3 and the wild type. In contrast, the activity of APX was significantly higher in the transgcnic plant than in wild type under salt stress. These results suggested that in higher plants, HvAPX1 played an important role in salt tolerance and was a candidate gene for developing salt-tolerant crop plants.

  19. Overexpression of MuHSP70 gene from Macrotyloma uniflorum confers multiple abiotic stress tolerance in transgenic Arabidopsis thaliana.

    Science.gov (United States)

    Masand, Shikha; Yadav, Sudesh Kumar

    2016-02-01

    A 70-KD heat shock protein (HSP70) is one of the most conserved chaperones. It is involved in de novo protein folding and prevents the aggregation of unfolded proteins under lethal environmental factors. The purpose of this study is to characterise a MuHSP70 from horsegram (Macrotyloma uniflorum) and elucidating its role in stress tolerance of plants. A MuHSP70 was cloned and characterised from a natural drought stress tolerant HPK4 variety of horsegram (M. uniflorum). For functional characterization, MuHSP70 was overexpressed in transgenic Arabidopsis. Overexpression of MuHSP70 was found to provide tolerance to the transgenic Arabidopsis against various stresses such as heat, cold, drought, salinity and oxidative stress. MuHSP70 transgenics were observed to maintain the shoot biomass, root length, relative water content, and chlorophyll content during exposure to multi-stresses relative to non-transgenic control. Transgenic lines have further shown the reduced levels of MDA, H2O2, and proteolytic activity. Together, these findings suggest that overexpression of MuHSP70 plays an important role in improving abiotic stress tolerance and could be a crucial candidate gene for exploration in crop improvement program. PMID:26694324

  20. Wheat Chloroplast Targeted sHSP26 Promoter Confers Heat and Abiotic Stress Inducible Expression in Transgenic Arabidopsis Plants

    OpenAIRE

    Khurana, Neetika; Chauhan, Harsh; Khurana, Paramjit

    2013-01-01

    The small heat shock proteins (sHSPs) have been found to play a critical role in physiological stress conditions in protecting proteins from irreversible aggregation. To characterize the hloroplast targeted sHSP26 promoter in detail, deletion analysis of the promoter is carried out and analysed via transgenics in Arabidopsis. In the present study, complete assessment of the importance of CCAAT-box elements along with Heat shock elements (HSEs) in the promoter of sHSP26 was performed. Moreover...

  1. Differences in photosynthesis and terpene content in leaves and roots of wild-type and transgenic Arabidopsis thaliana plants

    OpenAIRE

    Blanch Roure, Josep-Salvador; Peñuelas, Josep; Llusià Benet, Joan; Sardans i Galobart, Jordi; Owen, Susan M.

    2015-01-01

    We investigated the hypotheses that two different varieties of Arabidopsis thaliana show differences in physiology and terpene production. The two varieties of A. thaliana used in this study were wildtype (WT) and transgenic line (CoxIVFaNES I) genetically modified to emit nerolidol with linalool/nerolidol synthase (COX). Photosynthetic rate, electron transport rate, fluorescence, leaf volatile terpene contents and root volatile terpene contents were analyzed. For both types, we found coeluti...

  2. The Mechanism of the Silencing of a Transgene, NCED3‐LUC, in Arabidopsis Thaliana

    KAUST Repository

    Zhao, Junsong

    2011-06-20

    The Arabidopsis thaliana NCED3‐LUC transgenic line was constructed by several groups to study the regulatory network of the NCED3 gene, the protein of which catalyzes the rate‐limiting step of ABA biosynthesis under drought. The transgenic luciferase gene is expressed when the plants encounter drought stress. Intriguingly, this transgenic luciferase gene is silenced after propagation for several generations. To determine the mechanism of this gene silencing, we used a forward genetics approach. The seeds of NCED3‐LUC (referred as the ‘wild type’) were mutagenized by ethane methyl sulfonate (EMS). One mutant line, denoted as #73, with recovered luciferase activity was selected for further study. Analysis of the methylation status by bisulfite sequencing revealed that the transgenic NCED3 promoter in the #73 mutant had less methylation than the wild type. Demethylation was also evident for the endogenous NCED3 promoter and retrotransposon AtSN1 in the #73 mutant. The phenotype of #73 mutant includes small size, rapid dehydration rate, altered morphology, and a thin epicuticular wax layer. By use of map‐based cloning, the region containing the mutated gene was delimited to a contig of two BAC clones, F11F19 and F9C22, on chromosome 2. Our results indicate that NCED3‐LUC gene silencing results from hypermethylation of its promoter region, but additional study is required to determine the exact position of the mutated gene and to fully understand the mechanism of NCED3‐LUC silencing. 4 ACKNOWLEDGEMENTS I would like to take this opportunity to thank my committee chair, Professor Jian‐Kang Zhu, who is also the supervisor of my master’s thesis, for his guidance throughout the course of this research. I also would like to thank my committee members, Professor Liming Xiong and Professor Samir Hamdan, for their patience and support in reviewing my thesis. My appreciation also goes to Dr. Zhenyu Wang for taking time to teach me basic experimental skills and

  3. Functional analysis of the rice rubisco activase promoter in transgenic Arabidopsis

    Energy Technology Data Exchange (ETDEWEB)

    Yang, Zhipan; Lu, Qingtao; Wen, Xiaogang [Key Laboratory of Photobiology, Institute of Botany, Chinese Academy of Sciences, Beijing 100093 (China); Chen, Fan [Key Laboratory of Molecular and Developmental Biology, Institute of Genetics and Developmental Biology, Chinese Academy of Sciences, Beijing 100080 (China); Lu, Congming, E-mail: lucm@ibcas.ac.cn [Key Laboratory of Photobiology, Institute of Botany, Chinese Academy of Sciences, Beijing 100093 (China)

    2012-02-17

    Highlights: Black-Right-Pointing-Pointer Rice rubisco activase promoter was analyzed in transgenic Arabidopsis system. Black-Right-Pointing-Pointer Region conferring tissue specific and light inducible expression of Rca was identified. Black-Right-Pointing-Pointer -58 to +43 bp region mediates tissue-specific expression of rice Rca. Black-Right-Pointing-Pointer Light inducible expression of rice Rca is mediated by -297 to -58 bp region. Black-Right-Pointing-Pointer Rice nuclear proteins bind specifically with the light inducible region. -- Abstract: To gain a better understanding of the regulatory mechanism of the rice rubisco activase (Rca) gene, variants of the Rca gene promoter (one full-length and four deletion mutants) fused to the coding region of the bacterial reporter gene {beta}-glucuronidase (GUS) were introduced into Arabidopsis via Agrobacterium-mediated transformation. Our results show that a 340 bp fragment spanning from -297 to +43 bp relative to the transcription initiation site is enough to promote tissue-specific and light-inducible expression of the rice Rca gene as done by the full-length promoter (-1428 to +43 bp). Further deletion analysis indicated that the region conferring tissue-specificity of Rca expression is localized within a 105 bp fragment from -58 to +43 bp, while light-inducible expression of Rca is mediated by the region from -297 to -58 bp. Gel shift assays and competition experiments demonstrated that rice nuclear proteins bind specifically with the fragment conferring light responsiveness at more than one binding site. This implies that multiple cis-elements may be involved in light-induced expression of the rice Rca gene. These works provide a useful reference for understanding transcriptional regulation mechanism of the rice Rca gene, and lay a strong foundation for further detection of related cis-elements and trans-factors.

  4. Soybean GmPHD-type transcription regulators improve stress tolerance in transgenic Arabidopsis plants.

    Directory of Open Access Journals (Sweden)

    Wei Wei

    Full Text Available BACKGROUND: Soybean [Glycine max (L. Merr.] is one of the most important crops for oil and protein resource. Improvement of stress tolerance will be beneficial for soybean seed production. PRINCIPAL FINDINGS: Six GmPHD genes encoding Alfin1-type PHD finger protein were identified and their expressions differentially responded to drought, salt, cold and ABA treatments. The six GmPHDs were nuclear proteins and showed ability to bind the cis-element "GTGGAG". The N-terminal domain of GmPHD played a major role in DNA binding. Using a protoplast assay system, we find that GmPHD1 to GmPHD5 had transcriptional suppression activity whereas GmPHD6 did not have. In yeast assay, the GmPHD6 can form homodimer and heterodimer with the other GmPHDs except GmPHD2. The N-terminal plus the variable regions but not the PHD-finger is required for the dimerization. Transgenic Arabidopsis plants overexpressing the GmPHD2 showed salt tolerance when compared with the wild type plants. This tolerance was likely achieved by diminishing the oxidative stress through regulation of downstream genes. SIGNIFICANCE: These results provide important clues for soybean stress tolerance through manipulation of PHD-type transcription regulator.

  5. Transgenic AEQUORIN reveals organ-specific cytosolic Ca2+ responses to anoxia and Arabidopsis thaliana seedlings

    Science.gov (United States)

    Sedbrook, J. C.; Kronebusch, P. J.; Borisy, G. G.; Trewavas, A. J.; Masson, P. H.

    1996-01-01

    Using the transgenic AEQUORIN system, we showed that the cotyledons and leaves of Arabidopsis thaliana seedlings developed a biphasic luminescence response to anoxia, indicating changes in cytosolic Ca2+ levels. A fast and transient luminescence peak occurred within minutes of anoxia, followed by a second, prolonged luminescence response that lasted 1.5 to 4 h. The Ca2+ channel blockers Gd3+, La3+, and ruthenium red (RR) partially inhibited the first response and promoted a larger and earlier second response, suggesting different origins for these responses. Both Gd3+ and RR also partially inhibited anaerobic induction of alcohol dehydrogenase gene expression. However, although anaerobic alcohol dehydrogenase gene induction occurred in seedlings exposed to water-agar medium and in roots, related luminescence responses were absent. Upon return to normoxia, the luminescence of cotyledons, leaves, and roots dropped quickly, before increasing again in a Gd3+, La3+, ethyleneglycol-bis(beta-aminoethyl ether)-N,N'-tetraacetic acid-, and RR-sensitive fashion.

  6. Higher endogenous methionine in transgenic Arabidopsis seeds affects the composition of storage proteins and lipids.

    Science.gov (United States)

    Cohen, Hagai; Pajak, Agnieszka; Pandurangan, Sudhakar; Amir, Rachel; Marsolais, Frédéric

    2016-06-01

    Previous in vitro studies demonstrate that exogenous application of the sulfur-containing amino acid methionine into cultured soybean cotyledons and seedlings reduces the level of methionine-poor storage proteins and elevates those that are methionine-rich. However, the effect of higher endogenous methionine in seeds on the composition of storage products in vivo is not studied yet. We have recently produced transgenic Arabidopsis seeds having significantly higher levels of methionine. In the present work we used these seeds as a model system and profiled them for changes in the abundances of 12S-globulins and 2S-albumins, the two major groups of storage proteins, using 2D-gels and MALDI-MS detection. The findings suggest that higher methionine affects from a certain threshold the accumulation of several subunits of 12S-globulins and 2S-albumins, regardless of their methionine contents, resulting in higher total protein contents. The mRNA abundances of most of the genes encoding these proteins were either correlated or not correlated with the abundances of these proteins, implying that methionine may regulate storage proteins at both transcriptional and post-transcriptional levels. The elevations in total protein contents resulted in reduction of total lipids and altered the fatty acid composition. Altogether, the data provide new insights into the regulatory roles of elevated methionine levels on seed composition. PMID:26888094

  7. A Sulfonylurea Herbicide Resistance Gene from Arabidopsis thaliana as a New Selectable Marker for Production of Fertile Transgenic Rice Plants.

    Science.gov (United States)

    Li, Z; Hayashimoto, A; Murai, N

    1992-10-01

    A mutant acetolactate synthase (ALS) gene, csr1-1, isolated from sulfonylurea herbicide-resistant Arabidopsis thaliana, was placed under control of a cauliflower mosaic virus 35S promoter (35S). Rice protoplasts were transformed with the 35S/ALS chimeric gene and regenerated into fertile transgenic rice (Oryza sativa) plants. The 35S/ALS gene was expressed effectively as demonstrated by northern blot hybridization analysis, and conferred to transformed calli at least 200-fold greater chlorsulfuron resistance than nontransformed control calli. Effective selection of 35S/ALS-transformed protoplasts was achieved at extremely low chlorsulfuron concentrations of 10 nm. The results demonstrated that the 35S/ALS gene is an alternative selectable marker for rice protoplast transformation and fertile transgenic rice production. The results also suggest that the mutant form of Arabidopsis ALS enzyme operates normally in rice cells. Thus, the mechanism of protein transport to chloroplast and ALS inhibition by chlorsulfuron is apparently conserved among plant species as diverse as Arabidopsis (dicotyledon) and rice (monocotyledon). PMID:16653044

  8. Wheat chloroplast targeted sHSP26 promoter confers heat and abiotic stress inducible expression in transgenic Arabidopsis Plants.

    Directory of Open Access Journals (Sweden)

    Neetika Khurana

    Full Text Available The small heat shock proteins (sHSPs have been found to play a critical role in physiological stress conditions in protecting proteins from irreversible aggregation. To characterize the hloroplast targeted sHSP26 promoter in detail, deletion analysis of the promoter is carried out and analysed via transgenics in Arabidopsis. In the present study, complete assessment of the importance of CCAAT-box elements along with Heat shock elements (HSEs in the promoter of sHSP26 was performed. Moreover, the importance of 5' untranslated region (UTR has also been established in the promoter via Arabidopsis transgenics. An intense GUS expression was observed after heat stress in the transgenics harbouring a full-length promoter, confirming the heat-stress inducibility of the promoter. Transgenic plants without UTR showed reduced GUS expression when compared to transgenic plants with UTR as was confirmed at the RNA and protein levels by qRT-PCR and GUS histochemical assays, thus suggesting the possible involvement of some regulatory elements present in the UTR in heat-stress inducibility of the promoter. Promoter activity was also checked under different abiotic stresses and revealed differential expression in different deletion constructs. Promoter analysis based on histochemical assay, real-time qPCR and fluorimetric analysis revealed that HSEs alone could not transcribe GUS gene significantly in sHSP26 promoter and CCAAT box elements contribute synergistically to the transcription. Our results also provide insight into the importance of 5`UTR of sHsp26 promoter thus emphasizing the probable role of imperfect CCAAT-box element or some novel cis-element with respect to heat stress.

  9. Putrescine accumulation confers drought tolerance in transgenic Arabidopsis plants over-expressing the homologous Arginine decarboxylase 2 gene.

    Science.gov (United States)

    Alcázar, Rubén; Planas, Joan; Saxena, Triambak; Zarza, Xavier; Bortolotti, Cristina; Cuevas, Juan; Bitrián, Marta; Tiburcio, Antonio F; Altabella, Teresa

    2010-07-01

    In Arabidopsis, a model genus missing a functional ornithine decarboxylase pathway, most of the key genes involved in polyamine biosynthesis are duplicated. This gene redundancy has been related to the involvement of certain gene isoforms in the response to specific environmental stimuli. We have previously shown that drought stress induces Arginine decarboxlase 2 expression, while transcript levels for Arginine decarboxlase 1 remain constant. Accumulation of putrescine and increased arginine decarboxlase activity (EC 4.1.1.19) levels in response to different abiotic stresses have been reported in many different plant systems, but the biological meaning of this increase remains unclear. To get a new insight into these questions, we have studied the response to drought of transgenic Arabidopsis thaliana lines constitutively expressing the homologous Arginine decarboxlase 2 gene. These lines contain high levels of putrescine with no changes in spermidine and spermine content even under drought stress. Drought tolerance experiments indicate that the different degree of resistance to dehydration correlates with Put content. Although no significant differences were observed in the number of stomata between wild-type and transgenic plants, a reduction in transpiration rate and stomata conductance was observed in the ADC2 over-expressor lines. These results indicate that one of the mechanisms involved in the drought tolerance of transgenic plants over-producing Put is related to a reduction of water loss by transpiration. PMID:20206537

  10. Two P5CS genes from common bean exhibiting different tolerance to salt stress in transgenic Arabidopsis

    Indian Academy of Sciences (India)

    Ji Bao Chen; Jian Wei Yang; Zhao Yuan Zhang; Xiao Fan Feng; Shu Min Wang

    2013-12-01

    Many plants accumulate proline in response to salt stress. -pyrroline-5-carboxylate synthetase (P5CS) is the rate-limiting enzyme in proline biosynthesis in plants. Plasmid DNA (pCHF3-PvP5CS1 and pCHF3-PvP5CS2) containing the selectable neomycin phosphotransferase gene for kanamycin resistance and Phaseolus vulgaris P5CS (PvP5CS1 and PvP5CS2) cDNA was introduced into Arabidopsis plants using Agrobacterium-mediated gene transfer. Southern blot, northern blot and RT-PCR analyses demonstrated that the foreign genes were integrated into Arabidopsis chromosomal DNA and expressed. Single-gene transformants were analysed in this study. Transgenic plants expressed higher levels of PvP5CS1 and PvP5CS2 transcripts under salt stress conditions than under normal conditions. When treated with 0, 100 and 200 mM NaCl, the average proline content in leaves of transgenic plants was significantly higher $(P \\lt 0.01)$ than control plants. The average relative electrical conductivity (REC) of transgenic lines was significantly lower $(P \\lt 0.01)$ than control plants under salt stress condition. Biomass production of transgenic lines was significantly higher $(P \\lt 0.05)$ than control plants under 200 mM NaCl stress treatment. These results indicated that introducing PvP5CS1 and PvP5CS2 cDNA into transgenic Arabidopsis caused proline overproduction, increasing salt tolerance. Although the expression of PvP5CS1 in L4 lines and PvP5CS2 in S4 lines was the same under salt stress condition, the S4 lines accumulated 1.6 and 1.9 times more proline than the L4 lines under 100 and 200 mM NaCl treatments, respectively. The REC of S4 plants was 0.5 (100 mM NaCl) and 0.6 times (200 mM NaCl) that of L4 plants. The biomass production of S4 plants was 1.6 times (200 mM NaCl) more than in L4 plants. Total P5CS enzyme activity of S4 was significantly higher than that of L4. These results implied that the PvP5CS2 protein had stronger capacity to catalyze proline synthesis than PvP5CS1 under salt

  11. A three-component gene expression system and its application for inducible flavonoid overproduction in transgenic Arabidopsis thaliana.

    Directory of Open Access Journals (Sweden)

    Yue Feng

    Full Text Available Inducible gene expression is a powerful tool to study and engineer genes whose overexpression could be detrimental for the host organisms. However, only limited systems have been adopted in plant biotechnology. We have developed an osmotically inducible system using three components of plant origin, RD29a (Responsive to Dehydration 29A promoter, CBF3 (C-repeat Binding Factor 3 transcription factor and cpl1-2 (CTD phosphatase-like 1 mutation. The osmotic stress responsible RD29a promoter contains the CBF3 binding sites and thus RD29A-CBF3 feedforward cassette enhances induction of RD29a promoter under stress. The cpl1-2 mutation in a host repressor CPL1 promotes stress responsible RD29a promoter expression. The efficacy of this system was tested using PAP1 (Production of Anthocyanin Pigment 1 transgene, a model transcription factor that regulates the anthocyanin pathway in Arabidopsis. While transgenic plants with only one or two of three components did not reproducibly accumulate anthocyanin pigments above the control level, transgenic cpl1 plants containing homozygous RD29a-PAP1 and RD29a-CBF3 transgenes produced 30-fold higher level of total anthocyanins than control plants upon cold treatment. Growth retardation and phytochemical production of transgenic plants were minimum under normal conditions. The flavonoid profile in cold-induced transgenic plants was determined by LC/MS/MS, which resembled that of previously reported pap1-D plants but enriched for kaempferol derivatives. These results establish the functionality of the inducible three-component gene expression system in plant metabolic engineering. Furthermore, we show that PAP1 and environmental signals synergistically regulate the flavonoid pathway to produce a unique flavonoid blend that has not been produced by PAP1 overexpression or cold treatment alone.

  12. [Antimicrobial activities of ant Ponericin W1 against plant pathogens in vitro and the disease resistance in its transgenic Arabidopsis].

    Science.gov (United States)

    Chen, Yong-Fang; Sun, Peng-Wei; Tang, Ding-Zhong

    2013-08-01

    The antimicrobial peptides (AMPs) exhibit a broad antimicrobial spectrum. The application of AMPs from non-plant organisms attracts considerable attention in plant disease resistance engineering. Ponericin W1, isolated from the venom of ant (Pachycondyla goeldii), shows antimicrobial activities against Gram-positive bacteria, Gram-negative bacteria and the budding yeast (Saccharomyces cerevisiae); however, it is not clear whether Ponericin W1 is effective against plant pathogens. The results of this study indicated synthesized Ponericin W1 inhibited mycelial growth of Magnaporthe oryzae and Botrytis cinerea, as well as hyphal growth and spore production of Fusarium graminearum. Besides, Ponericin W1 exhibited antibacterial activities against Pseudomonas syringae pv. tomato and Xanthomonas oryzae pv. oryzae. After codon optimization, Ponericin W1 gene was constructed into plant expression vector, and transformed into Arabidopsis thaliana by floral dip method. The Ponericin W1 was located in intercellular space of the transgenic plants as expected. Compared with the wild-type plants, there were ungerminated spores and less hyphal, conidia on the leaves of transgenic plants after innoculation with the powdery mildew fungus Golovinomyces cichoracearum. After innoculation with the pathogenic bac-terium Pseudomonas syringae pv. tomato, the baceria in the leaves of transgenic plants was significantly less than the wild-type plants, indicating that the transgenic plants displayed enhanced disease resistance to pathogens. These results demonstrate a potential use of Ponericin W1 in genetic engineering for broad-spectrum plant disease resistance. PMID:23956091

  13. Biomonitoring of Non-Dioxin-Like Polychlorinated Biphenyls in Transgenic Arabidopsis Using the Mammalian Pregnane X Receptor System: A Role of Pectin in Pollutant Uptake

    OpenAIRE

    Bao, Lieming; Gao, Chen; Li, Miaomiao; Chen, Yong; Lin, Weiqiang; Yang, Yanjun; Han, Ning; Bian, Hongwu; Zhu, Muyuan; Wang, Junhui

    2013-01-01

    Polychlorinated biphenyls (PCBs) are persistent organic pollutants damaging to human health and the environment. Techniques to indicate PCB contamination in planta are of great interest to phytoremediation. Monitoring of dioxin-like PCBs in transgenic plants carrying the mammalian aryl hydrocarbon receptor (AHR) has been reported previously. Herein, we report the biomonitoring of non-dioxin-like PCBs (NDL-PCBs) using the mammalian pregnane X receptor (PXR). In the transgenic Arabidopsis desig...

  14. The better growth phenotype of DvGS1-transgenic arabidopsis thaliana is attributed to the improved efficiency of nitrogen assimilation

    Directory of Open Access Journals (Sweden)

    Zhu Chenguang

    2015-01-01

    Full Text Available The overexpression of the algal glutamine synthetase (GS gene DvGS1 in Arabidopsis thaliana resulted in higher plant biomass and better growth phenotype. The purpose of this study was to recognize the biological mechanism for the growth improvement of DvGS1-transgenic Arabidopsis. A series of molecular and biochemical investigations related to nitrogen and carbon metabolism in the DvGS1-transgenic line was conducted. Analysis of nitrogen use efficiency (NUE-related gene transcription and enzymatic activity revealed that the transcriptional level and enzymatic activity of the genes encoding GS, glutamate synthase, glutamate dehydrogenase, alanine aminotransferase and aspartate aminotransferase, were significantly upregulated, especially from leaf tissues of the DvGS1-transgenic line under two nitrate conditions. The DvGS1-transgenic line showed increased total nitrogen content and decreased carbon: nitrogen ratio compared to wild-type plants. Significant reduced concentrations of free nitrate, ammonium, sucrose, glucose and starch, together with higher concentrations of total amino acids, individual amino acids (glutamate, aspartate, asparagine, methionine, soluble proteins and fructose in leaf tissues confirmed that the DvGS1-transgenic line demonstrated a higher efficiency of nitrogen assimilation, which subsequently affected carbon metabolism. These improved metabolisms of nitrogen and carbon conferred the DvGS1-transgenic Arabidopsis higher NUE, more biomass and better growth phenotype compared with the wild-type plants.

  15. Using biomass of starch-rich transgenic Arabidopsis vacuolar as feedstock for fermentative hydrogen production

    Energy Technology Data Exchange (ETDEWEB)

    Lo, Yung-Chung; Cheng, Chieh-Lun; Chen, Chun-Yen [National Cheng Kung Univ., Tainan, Taiwan (China). Dept. of Chemical Engineering; Huang, Li-Fen; Chang, Jo-Shu [Yuan Ze Univ., Tao-yuan, Taiwan (China). Graduate School of Biotechnology and Bioengineering

    2010-07-01

    Cellulose is the major constitute of plant biomass and highly available in agricultural wastes and industrial effluents, thereby being a cost-effective feedstock for bioenergy production. However, most hydrogen producing bacteria (HPB) could not directly convert cellulosic materials (such as rice husk and rice straw) into hydrogen whereas most HPB could utilize sugar and starch for hydrogen production. In this work, we used an indigenous bacterial isolate Clostridium butyricum CGS2 as HPB, which could directly convert soluble starch into H2 with a maximum H2 production rate and a H2 yield of 205.07 ml H2/h/l and 6.46 mmol H2/g starch, respectively. However, C. butyricum CGS2 could not ferment pure cellulosic materials such as carboxymethyl cellulose and xylan. Moreover, we found that C. butyricum CGS2 could utilize rich husk to produce H2 at a rate of 13.19 ml H2/h/l due to the starch content in rice husk (H2 yield = 1.49 mmol H2/g rice husk). In contrast, since lacking starch content, rice straw cannot be converted to H2 by C. butyricum CGS2. The foregoing results suggest that increasing the starch content in the natural agricultural wastes may make them better feedstock for fermentative H2 production. Hence, a genetically modified plant (Arabidopsis vacuolar) was constructed to enhance its starch concentration. The starch concentration of mutant plant S1 increased to 10.67 mg/fresh weight, which is four times higher than that of wild type plant. Using mutant plant S1 as carbon source, C. butyricum CGS2 was able to give a high cumulative H2 production and H2 production rate of 285.4 ml H2/l and 43.6 ml/h/l, respectively. The cumulative H2 production and H2 production rate both increased when the concentration of the transgenic plant was increased. Therefore, this study successful demonstrated the feasibility of expressing starch on genetically-modified plants to create a more effective feedstock for dark H2 fermentation. (orig.)

  16. Heterologous Expression of Two Jatropha Aquaporins Imparts Drought and Salt Tolerance and Improves Seed Viability in Transgenic Arabidopsis thaliana.

    Directory of Open Access Journals (Sweden)

    Kasim Khan

    Full Text Available Drought and high salinity are environmental conditions that cause adverse effects on the growth and productivity of crops. Aquaporins are small integral membrane proteins that belong to the family of the major intrinsic proteins (MIPs, with members in animals, plants and microbes, where they facilitate the transport of water and/or small neutral solutes thereby affecting water balance. In this study we characterized two aquaporin genes namely, plasma membrane intrinsic protein (PIP2;7 and tonoplast intrinsic protein TIP1;3 from Jatropha curcas that are localised to the plasma membrane and vacuole respectively. Transgenic Arabidopsis thaliana lines over-expressing JcPIP2;7 and JcTIP1;3 under a constitutive promoter show improved germination under high salt and mannitol compared to control seeds. These transgenic plants also show increased root length under abiotic stress conditions compared to wild type Col-0 plants. Transgenic lines exposed to drought conditions by withholding water for 20 days, were able to withstand water stress and attained normal growth after re-watering unlike control plants which could not survive. Transgenic lines also had better seed yield than control under salt stress. Importantly, seed viability of transgenic plants grown under high salt concentration was 35%-45% compared to less than 5% for control seeds obtained from plants growing under salt stress. The effect of JcPIP2;7 and JcTIP1;3 on improving germination and seed viability in drought and salinity make these important candidates for genetic manipulation of plants for growth in saline soils.

  17. Heterologous Expression of Two Jatropha Aquaporins Imparts Drought and Salt Tolerance and Improves Seed Viability in Transgenic Arabidopsis thaliana.

    Science.gov (United States)

    Khan, Kasim; Agarwal, Pallavi; Shanware, Arti; Sane, Vidhu Aniruddha

    2015-01-01

    Drought and high salinity are environmental conditions that cause adverse effects on the growth and productivity of crops. Aquaporins are small integral membrane proteins that belong to the family of the major intrinsic proteins (MIPs), with members in animals, plants and microbes, where they facilitate the transport of water and/or small neutral solutes thereby affecting water balance. In this study we characterized two aquaporin genes namely, plasma membrane intrinsic protein (PIP2;7) and tonoplast intrinsic protein TIP1;3 from Jatropha curcas that are localised to the plasma membrane and vacuole respectively. Transgenic Arabidopsis thaliana lines over-expressing JcPIP2;7 and JcTIP1;3 under a constitutive promoter show improved germination under high salt and mannitol compared to control seeds. These transgenic plants also show increased root length under abiotic stress conditions compared to wild type Col-0 plants. Transgenic lines exposed to drought conditions by withholding water for 20 days, were able to withstand water stress and attained normal growth after re-watering unlike control plants which could not survive. Transgenic lines also had better seed yield than control under salt stress. Importantly, seed viability of transgenic plants grown under high salt concentration was 35%-45% compared to less than 5% for control seeds obtained from plants growing under salt stress. The effect of JcPIP2;7 and JcTIP1;3 on improving germination and seed viability in drought and salinity make these important candidates for genetic manipulation of plants for growth in saline soils. PMID:26067295

  18. Overexpression of ZmIRT1 and ZmZIP3 Enhances Iron and Zinc Accumulation in Transgenic Arabidopsis.

    Directory of Open Access Journals (Sweden)

    Suzhen Li

    Full Text Available Iron and zinc are important micronutrients for both the growth and nutrient availability of crop plants, and their absorption is tightly controlled by a metal uptake system. Zinc-regulated transporters, iron-regulated transporter-like proteins (ZIP, is considered an essential metal transporter for the acquisition of Fe and Zn in graminaceous plants. Several ZIPs have been identified in maize, although their physiological function remains unclear. In this report, ZmIRT1 was shown to be specifically expressed in silk and embryo, whereas ZmZIP3 was a leaf-specific gene. Both ZmIRT1 and ZmZIP3 were shown to be localized to the plasma membrane and endoplasmic reticulum. In addition, transgenic Arabidopsis plants overexpressing ZmIRT1 or ZmZIP3 were generated, and the metal contents in various tissues of transgenic and wild-type plants were examined based on ICP-OES and Zinpyr-1 staining. The Fe and Zn concentration increased in roots and seeds of ZmIRT1-overexpressing plants, while the Fe content in shoots decreased. Overexpressing ZmZIP3 enhanced Zn accumulation in the roots of transgenic plants, while that in shoots was repressed. In addition, the transgenic plants showed altered tolerance to various Fe and Zn conditions compared with wild-type plants. Furthermore, the genes associated with metal uptake were stimulated in ZmIRT1 transgenic plants, while those involved in intra- and inter- cellular translocation were suppressed. In conclusion, ZmIRT1 and ZmZIP3 are functional metal transporters with different ion selectivities. Ectopic overexpression of ZmIRT1 may stimulate endogenous Fe uptake mechanisms, which may facilitate metal uptake and homeostasis. Our results increase our understanding of the functions of ZIP family transporters in maize.

  19. Cytokinin-Deficient Transgenic Arabidopsis Plants Show Multiple Developmental Alterations Indicating Opposite Functions of Cytokinins in the Regulation of Shoot and Root Meristem Activity

    Czech Academy of Sciences Publication Activity Database

    Werner, T.; Motyka, Václav; Laucou, V.; Smets, R.; Onckelen, H. V.; Schmülling, T.

    2003-01-01

    Roč. 15, č. 11 (2003), s. 2532-2550. ISSN 1040-4651 R&D Projects: GA AV ČR IAA6038002 Institutional research plan: CEZ:AV0Z5038910 Keywords : Transgenic Arabidopsis Plants * Cytokinins * Root Meristem Activity Subject RIV: EB - Genetics ; Molecular Biology Impact factor: 10.679, year: 2003

  20. Use of the "gl1" Mutant and the "CA-rop2" Transgenic Plants of "Arabidopsis thaliana" in the Biology Laboratory Course

    Science.gov (United States)

    Zheng, Zhi-Liang

    2006-01-01

    This article describes the use of the "glabrous1 (g11)" mutant and constitutively active "(CA)-rop2" transgenic plants of "Arabidopsis thaliana" in teaching genetics laboratory for both high school and undergraduate students. The experiments provide students with F[subscript 1] and F[subscript 2] generations within a semester for genetic and…

  1. Isolation of AtNUDT5 gene promoter and characterization of its activity in transgenic Arabidopsis thaliana.

    Science.gov (United States)

    Zhang, Xiu-Chun; Li, Mei-Ying; Ruan, Meng-Bin; Xia, Yi-Ji; Wu, Kun-Xin; Peng, Ming

    2013-03-01

    AtNUDT5 is a cytosol Nudix that catalyzes the hydrolysis of a variety of substrates. In this report, a 1,387-bp 5'-flanking region of the AtNUDT5 gene was isolated from Arabidopsis thaliana. The tissue-specific activity of the 5'-flanking region was investigated by using the GUS gene as a reporter in transgenic A. thaliana plants. Weak GUS activity appeared in vascular tissues of young plants, strong GUS activity appeared in the axial roots, but no GUS activity was observed in the root cap, lateral roots, rosette leaf, mature silique and reproductive tissues such as stamen, pistil, and petal. Furthermore, by using these transgenic A. thaliana plants, results of the histochemical staining and fluorometric assays of GUS activity showed that the AtNUDT5 promoter can be activated by both avirulent Pst avrRpm1 and virulent Pst strains at 5 h post-infiltration and that the activity of AtNUDT5 promoter increased significantly at 24 h post-infiltration. Taken together, our results demonstrated that the AtNUDT5 promoter is pathogen-responsive. The promoter may be used to develop transgenic plants with an increased tolerance to pathogenic stresses. PMID:23322251

  2. Role of the durum wheat dehydrin in the function of proteases conferring salinity tolerance in Arabidopsis thaliana transgenic lines.

    Science.gov (United States)

    Saibi, Walid; Zouari, Nabil; Masmoudi, Khaled; Brini, Faiçal

    2016-04-01

    Dehydrins are claimed to stabilize macromolecules against freezing damage, dehydration, ionic or osmotic stresses, thermal stress and re-folding yield. However, their precise function remains unknown. In this context, we report the behavior of protease activities in dehydrin transgenic Arabidopsis lines against the wild type plant under salt stress (100mM NaCl). Indeed, proteases play key roles in plants, maintaining strict protein quality control and degrading specific sets of proteins in response to diverse environmental and developmental stimuli. We proved that durum wheat DHN-5 modulates the activity of some proteases, summarized on the promotion of the Cysteinyl protease and the decrease of the Aspartyl protease activity. This fact is also upgraded in salt stress conditions. We conclude that the dehydrin transgenic context encodes salinity tolerance in transgenic lines through the modulation of the interaction not only at transcriptional level but also at protein level and also with the impact of salt stress as an endogenous and exogenous effector on some biocatalysts like proteases. PMID:26751399

  3. Two Groups of Thellungiella salsuginea RAVs Exhibit Distinct Responses and Sensitivity to Salt and ABA in Transgenic Arabidopsis.

    Directory of Open Access Journals (Sweden)

    Shaohui Yang

    Full Text Available Containing both AP2 domain and B3 domain, RAV (Related to ABI3/VP1 transcription factors are involved in diverse functions in higher plants. A total of eight TsRAV genes were isolated from the genome of Thellungiella salsuginea and could be divided into two groups (A- and B-group based on their sequence similarity. The mRNA abundance of all Thellungiella salsuginea TsRAVs followed a gradual decline during seed germination. In Thellungiella salsuginea seedling, transcripts of TsRAVs in the group A (A-TsRAVs were gradually and moderately reduced by salt treatment but rapidly and severely repressed by ABA treatment. In comparison, with a barely detectable constitutive expression, the transcriptional level of TsRAVs in the group B (B-TsRAVs exhibited a moderate induction in cotyledons when confronted with ABA. We then produced the "gain-of-function" transgenic Arabidopsis plants for each TsRAV gene and found that only 35S:A-TsRAVs showed weak growth retardation including reduced root elongation, suggesting their roles in negatively controlling plant growth. Under normal conditions, the germination process of all TsRAVs overexpressing transgenic seeds was inhibited with a stronger effect observed in 35S:A-TsRAVs seeds than in 35S:B-TsRAVs seeds. With the presence of NaCl, seed germination and seedling root elongation of all plants including wild type and 35S:TsRAVs plants were retarded and a more severe inhibition occurred to the 35S:A-TsRAV transgenic plants. ABA treatment only negatively affected the germination rates of 35S:A-TsRAV transgenic seeds but not those of 35S:B-TsRAV transgenic seeds. All 35S:TsRAVs transgenic plants showed a similar degree of reduction in root growth compared with untreated seedlings in the presence of ABA. Furthermore, the cotyledon greening/expansion was more severely inhibited 35S:A-TsRAVs than in 35S:B-TsRAVs seedlings. Upon water deficiency, with a wider opening of stomata, 35S:A-TsRAVs plants experienced a faster

  4. The assembly of metals chelation by thiols and vacuolar compartmentalization conferred increased tolerance to and accumulation of cadmium and arsenic in transgenic Arabidopsis thaliana

    International Nuclear Information System (INIS)

    Highlights: ► Simultaneous transformation of AsPCS1 and ScYCF1 into Arabidopsis thaliana which is sensitive to heavy metals, leads to transgenic plants tolerant to Arsenic and cadmium. ► Dual-gene transgenic Arabidopsis showed higher accumulation of Arsenic and cadmium than single and non-transgenic plants. ► Our results proved that improved thiol peptides synthesis and vacuolar compartmentation in plant dramatically boosted the survival rates of plants when exposed to heavy metals. ► A new strategy for efficient phytoremediation of heavy metals by stacking genes transformation in plants was developed in this article. - Abstract: Transgenic Arabidopsis thaliana were developed to increase tolerance for and accumulation of heavy metals and metalloids by simultaneous overexpression of AsPCS1 and YCF1 (derived from garlic and baker's yeast) based on the fact that chelation of metals and vacuolar compartmentalization are the main strategies for heavy metals/metalloids detoxification and tolerance in plants. Dual-gene transgenic lines had the longest roots and the highest accumulation of Cd and As than single-gene transgenic lines and wildtype. When grown on cadmium or arsenic (arsenite/arsenate), Dual-gene transgenic lines accumulated over 2–10 folds cadmium/arsenite and 2–3 folds arsenate than wild type or plants expressing AsPCS1 or YCF1 alone. Such stacking modified genes involved in chelation of toxic metals and vacuolar compartmentalization represents a highly promising new tool for use in phytoremediation efforts.

  5. The assembly of metals chelation by thiols and vacuolar compartmentalization conferred increased tolerance to and accumulation of cadmium and arsenic in transgenic Arabidopsis thaliana

    Energy Technology Data Exchange (ETDEWEB)

    Guo, Jiangbo [Key Laboratory of Plant Resources, Institute of Botany, The Chinese Academy of Sciences, Beijing 100093 (China); Inner Mongolia Key Laboratory of Biomass-Energy Conversion, The Institute of Bioengineering and Technology, Inner Mongolia University of Science and Technology, Baotou 040100 (China); Xu, Wenzhong [Key Laboratory of Plant Resources, Institute of Botany, The Chinese Academy of Sciences, Beijing 100093 (China); Ma, Mi, E-mail: mami@ibcas.ac.cn [Key Laboratory of Plant Resources, Institute of Botany, The Chinese Academy of Sciences, Beijing 100093 (China)

    2012-01-15

    Highlights: Black-Right-Pointing-Pointer Simultaneous transformation of AsPCS1 and ScYCF1 into Arabidopsis thaliana which is sensitive to heavy metals, leads to transgenic plants tolerant to Arsenic and cadmium. Black-Right-Pointing-Pointer Dual-gene transgenic Arabidopsis showed higher accumulation of Arsenic and cadmium than single and non-transgenic plants. Black-Right-Pointing-Pointer Our results proved that improved thiol peptides synthesis and vacuolar compartmentation in plant dramatically boosted the survival rates of plants when exposed to heavy metals. Black-Right-Pointing-Pointer A new strategy for efficient phytoremediation of heavy metals by stacking genes transformation in plants was developed in this article. - Abstract: Transgenic Arabidopsis thaliana were developed to increase tolerance for and accumulation of heavy metals and metalloids by simultaneous overexpression of AsPCS1 and YCF1 (derived from garlic and baker's yeast) based on the fact that chelation of metals and vacuolar compartmentalization are the main strategies for heavy metals/metalloids detoxification and tolerance in plants. Dual-gene transgenic lines had the longest roots and the highest accumulation of Cd and As than single-gene transgenic lines and wildtype. When grown on cadmium or arsenic (arsenite/arsenate), Dual-gene transgenic lines accumulated over 2-10 folds cadmium/arsenite and 2-3 folds arsenate than wild type or plants expressing AsPCS1 or YCF1 alone. Such stacking modified genes involved in chelation of toxic metals and vacuolar compartmentalization represents a highly promising new tool for use in phytoremediation efforts.

  6. Co-overexpressing a Plasma Membrane and a Vacuolar Membrane Sodium/Proton Antiporter Significantly Improves Salt Tolerance in Transgenic Arabidopsis Plants

    Science.gov (United States)

    Pehlivan, Necla; Sun, Li; Jarrett, Philip; Yang, Xiaojie; Mishra, Neelam; Chen, Lin; Kadioglu, Asim; Shen, Guoxin; Zhang, Hong

    2016-01-01

    The Arabidopsis gene AtNHX1 encodes a vacuolar membrane-bound sodium/proton (Na+/H+) antiporter that transports Na+ into the vacuole and exports H+ into the cytoplasm. The Arabidopsis gene SOS1 encodes a plasma membrane-bound Na+/H+ antiporter that exports Na+ to the extracellular space and imports H+ into the plant cell. Plants rely on these enzymes either to keep Na+ out of the cell or to sequester Na+ into vacuoles to avoid the toxic level of Na+ in the cytoplasm. Overexpression of AtNHX1 or SOS1 could improve salt tolerance in transgenic plants, but the improved salt tolerance is limited. NaCl at concentration >200 mM would kill AtNHX1-overexpressing or SOS1-overexpressing plants. Here it is shown that co-overexpressing AtNHX1 and SOS1 could further improve salt tolerance in transgenic Arabidopsis plants, making transgenic Arabidopsis able to tolerate up to 250 mM NaCl treatment. Furthermore, co-overexpression of AtNHX1 and SOS1 could significantly reduce yield loss caused by the combined stresses of heat and salt, confirming the hypothesis that stacked overexpression of two genes could substantially improve tolerance against multiple stresses. This research serves as a proof of concept for improving salt tolerance in other plants including crops. PMID:26985021

  7. SpBADH of the halophyte Sesuvium portulacastrum strongly confers drought tolerance through ROS scavenging in transgenic Arabidopsis.

    Science.gov (United States)

    Yang, Chenglong; Zhou, Yang; Fan, Jie; Fu, Yuhua; Shen, Longbin; Yao, Yuan; Li, Ruimei; Fu, Shaoping; Duan, Ruijun; Hu, Xinwen; Guo, Jianchun

    2015-11-01

    Glycine betaine (GB) accumulation is involved in abiotic stress. However, it is not known whether BADH, the key enzyme of GB synthesis, utilizes the antioxidant system to confer drought stress tolerance. In this study, a novel member of the ALDH10 gene family, SpBADH, was isolated from Sesuvium portulacastrum. The expression of this gene was up-regulated by NaCl, PEG6000, H2O2, ABA and high temperature in S. portulacastrum. SpBADH overexpression in Arabidopsis resulted in higher BADH activity and GB content and might increase tolerance to drought/osmotic stresses, specifically strong tolerance to drought stress. Transgenic lines exhibited lower MDA and H2O2 contents but higher proline, POD, SOD and CAT contents than the wild type under drought and osmotic stresses. SpBADH overexpression in Arabidopsis also enhanced the expression of ROS-related genes including AtSOD, AtPOD, AtCAT, AtAPX and Atpsb under drought and osmotic stresses. Thus, SpBADH increases plant tolerance to drought or osmotic stresses by reducing H2O2, increasing proline, and activating antioxidative enzymes to improve ROS scavenging. PMID:26368017

  8. ZmNAC55, a maize stress-responsive NAC transcription factor, confers drought resistance in transgenic Arabidopsis.

    Science.gov (United States)

    Mao, Hude; Yu, Lijuan; Han, Ran; Li, Zhanjie; Liu, Hui

    2016-08-01

    Abiotic stress has been shown to significantly limit the growth and productivity of crops. NAC transcription factors play essential roles in response to various abiotic stresses. However, only little information regarding stress-related NAC genes is available in maize. Here, we cloned a maize NAC transcription factor ZmNAC55 and identified its function in drought stress. Transient expression and transactivation assay demonstrated that ZmNAC55 was localized in the nucleus and had transactivation activity. Expression analysis of ZmNAC55 in maize showed that this gene was induced by drought, high salinity and cold stresses and by abscisic acid (ABA). Promoter analysis demonstrated that multiple stress-related cis-acting elements exist in promoter region of ZmNAC55. Overexpression of ZmNAC55 in Arabidopsis led to hypersensitivity to ABA at the germination stage, but enhanced drought resistence compared to wild-type seedlings. Transcriptome analysis identified a number of differentially expressed genes between 35S::ZmNAC55 transgenic and wild-type plants, and many of which are involved in stress response, including twelve qRT-PCR confirmed well-known drought-responsive genes. These results highlight the important role of ZmNAC55 in positive regulates of drought resistence, and may have potential applications in transgenic breeding of drought-tolerant crops. PMID:27085597

  9. Multiple abiotic stress tolerance of the transformants yeast cells and the transgenic Arabidopsis plants expressing a novel durum wheat catalase.

    Science.gov (United States)

    Feki, Kaouthar; Kamoun, Yosra; Ben Mahmoud, Rihem; Farhat-Khemakhem, Ameny; Gargouri, Ali; Brini, Faiçal

    2015-12-01

    Catalases are reactive oxygen species scavenging enzymes involved in response to abiotic and biotic stresses. In this study, we described the isolation and functional characterization of a novel catalase from durum wheat, designed TdCAT1. Molecular Phylogeny analyses showed that wheat TdCAT1 exhibited high amino acids sequence identity to other plant catalases. Sequence homology analysis showed that TdCAT1 protein contained the putative calmodulin binding domain and a putative conserved internal peroxisomal targeting signal PTS1 motif around its C-terminus. Predicted three-dimensional structural model revealed the presence of four putative distinct structural regions which are the N-terminal arm, the β-barrel, the wrapping and the α-helical domains. TdCAT1 protein had the heme pocket that was composed by five essential residues. TdCAT1 gene expression analysis showed that this gene was induced by various abiotic stresses in durum wheat. The expression of TdCAT1 in yeast cells and Arabidopsis plants conferred tolerance to several abiotic stresses. Compared with the non-transformed plants, the transgenic lines maintained their growth and accumulated more proline under stress treatments. Furthermore, the amount of H2O2 was lower in transgenic lines, which was due to the high CAT and POD activities. Taken together, these data provide the evidence for the involvement of durum wheat catalase TdCAT1 in tolerance to multiple abiotic stresses in crop plants. PMID:26555900

  10. Putrescine accumulation in Arabidopsis thaliana transgenic lines enhances tolerance to dehydration and freezing stress

    OpenAIRE

    Alet, Analía I; Sanchez, Diego H; Cuevas, Juan C.; del Valle, Secundino; Altabella, Teresa; Tiburcio, Antonio F; Marco, Francisco; Ferrando, Alejandro; Espasandín, Fabiana D; González, María E; Carrasco, Pedro; Ruiz, Oscar A.

    2011-01-01

    Polyamines have been globally associated to plant responses to abiotic stress. Particularly, putrescine has been related to a better response to cold and dehydration stresses. It is known that this polyamine is involved in cold tolerance, since Arabidopsis thaliana plants mutated in the key enzyme responsible for putrescine synthesis (arginine decarboxilase, ADC; EC 4.1.1.19) are more sensitive than the wild type to this stress. Although it is speculated that the overexpression of ADC genes m...

  11. Modification of the synthesis of bioactive flavonoids in transgenic hop Humulus lupulus L. by PAP1/MYB75 from Arabidopsis thaliana L

    Czech Academy of Sciences Publication Activity Database

    Aldinger, C.; Stanke, M.; Alheit, C.; Gatíca, A.; Höhnle, M.; Matoušek, Jaroslav; Weber, G.

    Hüll: Scientific Commission of the International Hop Growers Convention, 2009 - (Seigner, E.), s. 49-52 ISSN 1814-2192. [Scientific Commission of the International Hop Growers Convention Meeting. León (ES), 21.06.2009-25.06.2009] Institutional research plan: CEZ:AV0Z50510513 Keywords : flavonoid biosynthesis * transgenic hop Humulus lupulus L. cv. Tettnanger * Arabidopsis thaliana PAP1/MYB75 regulatory gene Subject RIV: CE - Biochemistry

  12. Effects of biosurfactants on assays of PCB congeners in transgenic arabidopsis plants carrying a recombinant guinea pig AhR-mediated GUS reporter gene expression system.

    Science.gov (United States)

    Shimazu, Sayuri; Ohta, Masaya; Inui, Hideyuki; Nanasato, Yoshihiko; Ashida, Hitoshi; Ohkawa, Hideo

    2010-11-01

    The transgenic Arabidopsis plants carrying a recombinant guinea pig (g) aryl hydrocarbon receptor (AhR)-mediated β-glucuronidase (GUS) reporter gene expression system were generated for assays of polychlorinated biphenyl (PCB) congeners. The selected transgenic Arabidopsis plant XgD2V11-6 exhibited a correlation between uptake of PCB126 and PCB126-induced GUS activity. Also, the plants showed induced GUS activity towards the supplemental indole 3-acetic acid (IAA). Thus, the GUS assay may reflect induction by both endogenous and exogenous AhR ligands. When biosurfactants, MEL-B, produced in the culture of yeast isolated from plants were used for assays of PCB congeners in the transgenic Arabidopsis plants, they showed marked PCB126 dose-dependent and toxic equivalency factor (TEF) dependent GUS activities. The effects of biosurfactants were clearer when the plants were cultivated on soils containing PCB congeners for 7 days as compared with on soils for 3 days as well as in the medium for 3 days. Therefore, it was estimated that biosurfactants form micellae with PCB congeners, which are easily uptaken by the plants in a mode of passive diffusion, transport into the aerial parts and then induce GUS activity. PMID:20936563

  13. Over-expression of Arabidopsis thaliana SFD1/GLY1, the gene encoding plastid localized glycerol-3-phosphate dehydrogenase, increases plastidic lipid content in transgenic rice plants.

    Science.gov (United States)

    Singh, Vijayata; Singh, Praveen Kumar; Siddiqui, Adnan; Singh, Subaran; Banday, Zeeshan Zahoor; Nandi, Ashis Kumar

    2016-03-01

    Lipids are the major constituents of all membranous structures in plants. Plants possess two pathways for lipid biosynthesis: the prokaryotic pathway (i.e., plastidic pathway) and the eukaryotic pathway (i.e., endoplasmic-reticulum (ER) pathway). Whereas some plants synthesize galactolipids from diacylglycerol assembled in the plastid, others, including rice, derive their galactolipids from diacylglycerols assembled by the eukaryotic pathway. Arabidopsis thaliana glycerol-3-phosphate dehydrogenase (G3pDH), coded by SUPPRESSOR OF FATTY ACID DESATURASE 1 (SFD1; alias GLY1) gene, catalyzes the formation of glycerol 3-phosphate (G3p), the backbone of many membrane lipids. Here SFD1 was introduced to rice as a transgene. Arabidopsis SFD1 localizes in rice plastids and its over-expression increases plastidic membrane lipid content in transgenic rice plants without any major impact on ER lipids. The results suggest that over-expression of plastidic G3pDH enhances biosynthesis of plastid-localized lipids in rice. Lipid composition in the transgenic plants is consistent with increased phosphatidylglycerol synthesis in the plastid and increased galactolipid synthesis from diacylglycerol produced via the ER pathway. The transgenic plants show a higher photosynthetic assimilation rate, suggesting a possible application of this finding in crop improvement. PMID:26747130

  14. Molecular cloning of a pathogen/wound-inducible PR10 promoter from Pinus monticola and characterization in transgenic Arabidopsis plants.

    Science.gov (United States)

    Liu, Jun-Jun; Ekramoddoullah, Abul K M; Piggott, Nina; Zamani, Arezoo

    2005-05-01

    In Pinus monticola (Dougl. ex D. Don), the class ten pathogenesis-related (PR10) proteins comprise a family of multiple members differentially expressed upon pathogen infection and other environmental stresses. One of them, PmPR10-1.13, is studied here by investigating its transcriptional regulation in transgenic Arabidopsis plants. For functional analyses of the PmPR10-1.13 promoter, a 1,316-bp promoter fragment and three 5' deletions were translationally fused to the ss-glucuronidase (GUS) reporter gene. The 1,316-bp promoter-driven GUS activity first appeared in hypocotyls and cotyledons in 2- to 3-day-old seedlings. As transgenic plants grew, GUS activity was detected strongly in apical meristems, next in stems and leaves. No GUS activity was detected in roots and in reproductive tissues of flower organs. In adult plants, the PmPR10-1.13 promoter-directed GUS expression was upregulated following pathogen infection and by wounding treatment, which generally mimic the endogenous expression pattern in western white pine. Promoter analysis of 5' deletions demonstrated that two regions between -1,316 and -930, and between -309 and -100 were responsible for the wound responsiveness. By structural and functional comparisons with PmPR10-1.14 promoter, putative wound-responsive elements were potentially identified in the PmPR10-1.13 promoter. In conclusion, PmPR10-1.13 showed properties of a defence-responsive gene, being transcriptionally upregulated upon biotic and abiotic stresses. PMID:15609047

  15. DICER-LIKE2 Plays a Primary Role in Transitive Silencing of Transgenes in Arabidopsis

    OpenAIRE

    Mlotshwa, Sizolwenkosi; Pruss, Gail J; Peragine, Angela; Endres, Matthew W.; Li, Junjie; Chen, Xuemei; Poethig, R Scott; Bowman, Lewis H.; Vance, Vicki

    2008-01-01

    Dicer-like (DCL) enzymes play a pivotal role in RNA silencing in plants, processing the long double-stranded RNA (dsRNA) that triggers silencing into the primary short interfering RNAs (siRNAs) that mediate it. The siRNA population can be augmented and silencing amplified via transitivity, an RNA-dependent RNA polymerase (RDR)-dependent pathway that uses the target RNA as substrate to generate secondary siRNAs. Here we report that Arabidopsis DCL2–but not DCL4-is required for transitivity in ...

  16. PpCBF3 from Cold-Tolerant Kentucky Bluegrass Involved in Freezing Tolerance Associated with Up-Regulation of Cold-Related Genes in Transgenic Arabidopsis thaliana.

    Directory of Open Access Journals (Sweden)

    Lili Zhuang

    Full Text Available Dehydration-Responsive Element Binding proteins (DREB/C-repeat (CRT Binding Factors (CBF have been identified as transcriptional activators during plant responses to cold stress. The objective of this study was to determine the physiological roles of a CBF gene isolated from a cold-tolerant perennial grass species, Kentucky bluegrass (Poa pratensis L., which designated as PpCBF3, in regulating plant tolerance to freezing stress. Transient transformation of Arabidopsis thaliana mesophyll protoplast with PpCBF3-eGFP fused protein showed that PpCBF3 was localized to the nucleus. RT-PCR analysis showed that PpCBF3 was specifically induced by cold stress (4°C but not by drought stress [induced by 20% polyethylene glycol 6000 solution (PEG-6000] or salt stress (150 mM NaCl. Transgenic Arabidopsis overexpressing PpCBF3 showed significant improvement in freezing (-20°C tolerance demonstrated by a lower percentage of chlorotic leaves, lower cellular electrolyte leakage (EL and H2O2 and O2.- content, and higher chlorophyll content and photochemical efficiency compared to the wild type. Relative mRNA expression level analysis by qRT-PCR indicated that the improved freezing tolerance of transgenic Arabidopsis plants overexpressing PpCBF3 was conferred by sustained activation of downstream cold responsive (COR genes. Other interesting phenotypic changes in the PpCBF3-transgenic Arabidopsis plants included late flowering and slow growth or 'dwarfism', both of which are desirable phenotypic traits for perennial turfgrasses. Therefore, PpCBF3 has potential to be used in genetic engineering for improvement of turfgrass freezing tolerance and other desirable traits.

  17. A highly efficient miPCR method for isolating FSTs from transgenic Arabidopsis thaliana plants

    Indian Academy of Sciences (India)

    Gennady V. Pogorelko; Oksana V. Fursova

    2008-08-01

    The exact localization of an insertion in the genome of transgenic plants obtained by Agrobacterium-mediated transformation is an integral part of most experiments aimed at studying these types of mutants. There are several methods for isolating unknown nucleotide sequences of genomic DNA which flank the borders of T-DNA integrated in the genome of plants. However, all the methods based on PCR have limitations which in some cases do not permit the desired objective to be achieved. We have developed a new technique for isolating flanking sequence tags (FSTs) via modified inverse PCR. This method is highly efficient and simple, but also retains the advantages of previously well-documented approaches.

  18. Arabidopsis and Brachypodium distachyon transgenic plants expressing Aspergillus nidulans acetylesterases have decreased degree of polysaccharide acetylation and increased resistance to pathogens.

    Science.gov (United States)

    Pogorelko, Gennady; Lionetti, Vincenzo; Fursova, Oksana; Sundaram, Raman M; Qi, Mingsheng; Whitham, Steven A; Bogdanove, Adam J; Bellincampi, Daniela; Zabotina, Olga A

    2013-05-01

    The plant cell wall has many significant structural and physiological roles, but the contributions of the various components to these roles remain unclear. Modification of cell wall properties can affect key agronomic traits such as disease resistance and plant growth. The plant cell wall is composed of diverse polysaccharides often decorated with methyl, acetyl, and feruloyl groups linked to the sugar subunits. In this study, we examined the effect of perturbing cell wall acetylation by making transgenic Arabidopsis (Arabidopsis thaliana) and Brachypodium (Brachypodium distachyon) plants expressing hemicellulose- and pectin-specific fungal acetylesterases. All transgenic plants carried highly expressed active Aspergillus nidulans acetylesterases localized to the apoplast and had significant reduction of cell wall acetylation compared with wild-type plants. Partial deacetylation of polysaccharides caused compensatory up-regulation of three known acetyltransferases and increased polysaccharide accessibility to glycosyl hydrolases. Transgenic plants showed increased resistance to the fungal pathogens Botrytis cinerea and Bipolaris sorokiniana but not to the bacterial pathogens Pseudomonas syringae and Xanthomonas oryzae. These results demonstrate a role, in both monocot and dicot plants, of hemicellulose and pectin acetylation in plant defense against fungal pathogens. PMID:23463782

  19. Overexpression of soybean R2R3-MYB transcription factor, GmMYB12B2, and tolerance to UV radiation and salt stress in transgenic Arabidopsis.

    Science.gov (United States)

    Li, X W; Wang, Y; Yan, F; Li, J W; Zhao, Y; Zhao, X; Zhai, Y; Wang, Q Y

    2016-01-01

    MYB, v-myb avian myeloblastosis viral oncogene homolog, proteins play central roles in plant stress response. Previously, we identified a novel R2R3-MYB transcription factor, GmMYB12B2, which affected the expression levels of some key enzyme genes involved in flavonoid biosynthesis in transgenic Arabidopsis. In the present study, we analyzed the expression levels of GmMYB12B2 under salt, low temperature, drought, abscisic acid (ABA), and ultraviolet (UV) radiation treatments in soybean using semi-quantitative reverse transcription polymerase chain reaction. The expression of GmMYB12B2 was drastically induced by UV irradiation and salt treatment, but no response was detected under low temperature, drought, and ABA stresses. A detailed characterization of the GmMYB12B2 overexpression lines revealed that GmMYB12B2 might be involved in response of plants to UV radiation and salt stresses. Transgenic Arabidopsis lines constitutively expressing GmMYB12B2 showed an increased tolerance to salt and UV radiation treatment compared with wild-type plants. The expression levels of certain salt stress-responsive genes, such as DREB2A and RD17, were found to be elevated in the transgenic plants. These results indicate that GmMYB12B2 acts as a regulator in the plant stress response. PMID:27323089

  20. Diversion of carbon flux from gibberellin to steviol biosynthesis by over-expressing SrKA13H induced dwarfism and abnormality in pollen germination and seed set behaviour of transgenic Arabidopsis.

    Science.gov (United States)

    Guleria, Praveen; Masand, Shikha; Yadav, Sudesh Kumar

    2015-07-01

    This paper documents the engineering of Arabidopsis thaliana for the ectopic over-expression of SrKA13H (ent-kaurenoic acid-13 hydroxylase) cDNA from Stevia rebaudiana. HPLC analysis revealed the significant accumulation of steviol (1-3 μg g(-1) DW) in two independent transgenic Arabidopsis lines over-expressing SrKA13H compared with the control. Independent of the steviol concentrations detected, both transgenic lines showed similar reductions in endogenous bioactive gibberellins (GA1 and GA4). They possessed phenotypic similarity to gibberellin-deficient mutants. The reduction in endogenous gibberellin content was found to be responsible for dwarfism in the transgenics. The exogenous application of GA3 could rescue the transgenics from dwarfism. The hypocotyl, rosette area, and stem length were all considerably reduced in the transgenics. A noteworthy decrease in pollen viability was noticed and, similarly, a retardation of 60-80% in pollen germination rate was observed. The exogenous application of steviol (0.2, 0.5, and 1.0 μg ml(-1)) did not influence pollen germination efficiency. This has suggested that in planta formation of steviol was not responsible for the observed changes in transgenic Arabidopsis. Further, the seed yield of the transgenics was reduced by 24-48%. Hence, this study reports for the first time that over-expression of SrKA13H cDNA in Arabidopsis has diverted the gibberellin biosynthetic route towards steviol biosynthesis. The Arabidopsis transgenics showed a significant reduction in endogenous gibberellins that might be responsible for the dwarfism, and the abnormal behaviour of pollen germination and seed set. PMID:25954046

  1. Expression of the Arabidopsis vacuolar H+-pyrophosphatase gene (AVP1) improves the shoot biomass of transgenic barley and increases grain yield in a saline field

    KAUST Repository

    Schilling, Rhiannon K.

    2013-11-22

    Cereal varieties with improved salinity tolerance are needed to achieve profitable grain yields in saline soils. The expression of AVP1, an Arabidopsis gene encoding a vacuolar proton pumping pyrophosphatase (H+-PPase), has been shown to improve the salinity tolerance of transgenic plants in greenhouse conditions. However, the potential for this gene to improve the grain yield of cereal crops in a saline field has yet to be evaluated. Recent advances in high-throughput nondestructive phenotyping technologies also offer an opportunity to quantitatively evaluate the growth of transgenic plants under abiotic stress through time. In this study, the growth of transgenic barley expressing AVP1 was evaluated under saline conditions in a pot experiment using nondestructive plant imaging and in a saline field trial. Greenhouse-grown transgenic barley expressing AVP1 produced a larger shoot biomass compared to segregants, as determined by an increase in projected shoot area, when grown in soil with 150 mm NaCl. This increase in shoot biomass of transgenic AVP1 barley occurred from an early growth stage and also in nonsaline conditions. In a saline field, the transgenic barley expressing AVP1 also showed an increase in shoot biomass and, importantly, produced a greater grain yield per plant compared to wild-type plants. Interestingly, the expression of AVP1 did not alter barley leaf sodium concentrations in either greenhouse- or field-grown plants. This study validates our greenhouse-based experiments and indicates that transgenic barley expressing AVP1 is a promising option for increasing cereal crop productivity in saline fields. © 2013 Society for Experimental Biology, Association of Applied Biologists and John Wiley & Sons Ltd.

  2. Impact of ubiquitous inhibitors on the GUS gene reporter system: evidence from the model plants Arabidopsis, tobacco and rice and correction methods for quantitative assays of transgenic and endogenous GUS

    Directory of Open Access Journals (Sweden)

    Gerola Paolo D

    2009-12-01

    Full Text Available Abstract Background The β-glucuronidase (GUS gene reporter system is one of the most effective and employed techniques in the study of gene regulation in plant molecular biology. Improving protocols for GUS assays have rendered the original method described by Jefferson amenable to various requirements and conditions, but the serious limitation caused by inhibitors of the enzyme activity in plant tissues has thus far been underestimated. Results We report that inhibitors of GUS activity are ubiquitous in organ tissues of Arabidopsis, tobacco and rice, and significantly bias quantitative assessment of GUS activity in plant transformation experiments. Combined with previous literature reports on non-model species, our findings suggest that inhibitors may be common components of plant cells, with variable affinity towards the E. coli enzyme. The reduced inhibitory capacity towards the plant endogenous GUS discredits the hypothesis of a regulatory role of these compounds in plant cells, and their effect on the bacterial enzyme is better interpreted as a side effect due to their interaction with GUS during the assay. This is likely to have a bearing also on histochemical analyses, leading to inaccurate evaluations of GUS expression. Conclusions In order to achieve reliable results, inhibitor activity should be routinely tested during quantitative GUS assays. Two separate methods to correct the measured activity of the transgenic and endogenous GUS are presented.

  3. The Peanut (Arachis hypogaea L. Gene AhLPAT2 Increases the Lipid Content of Transgenic Arabidopsis Seeds.

    Directory of Open Access Journals (Sweden)

    Silong Chen

    Full Text Available Lysophosphatidic acid acyltransferase (LPAT, which converts lysophosphatidic acid (LPA to phosphatidic acid (PA, catalyzes the addition of fatty acyl moieties to the sn-2 position of the LPA glycerol backbone in triacylglycerol (TAG biosynthesis. We recently reported the cloning and temporal-spatial expression of a peanut (Arachis hypogaea AhLPAT2gene, showing that an increase in AhLPAT2 transcript levels was closely correlated with an increase in seed oil levels. However, the function of the enzyme encoded by the AhLPAT2 gene remains unclear. Here, we report that AhLPAT2 transcript levels were consistently higher in the seeds of a high-oil cultivar than in those of a low-oil cultivar across different seed developmental stages. Seed-specific overexpression of AhLPAT2 in Arabidopsis results in a higher percentage of oil in the seeds and greater-than-average seed weight in the transgenic plants compared with the wild-type plants, leading to a significant increase in total oil yield per plant. The total fatty acid (FA content and the proportion of unsaturated FAs also increased. In the developing siliques of AhLPAT2-overexpressing plants, the expression levels of genes encoding crucial enzymes involved in de novo FA synthesis, acetyl-CoA subunit (AtBCCP2 and acyl carrier protein 1 (AtACP1 were elevated. AhLPAT2 overexpression also promoted the expression of several key genes related to TAG assembly, sucrose metabolism, and glycolysis. These results demonstrate that the expression of AhLPAT2 plays an important role in glycerolipid production in peanuts.

  4. A maize calcium-dependent protein kinase gene, ZmCPK4, positively regulated abscisic acid signaling and enhanced drought stress tolerance in transgenic Arabidopsis.

    Science.gov (United States)

    Jiang, Shanshan; Zhang, Dan; Wang, Li; Pan, Jiaowen; Liu, Yang; Kong, Xiangpei; Zhou, Yan; Li, Dequan

    2013-10-01

    Calcium-dependent protein kinases (CDPKs) play essential roles in calcium-mediated signal transductions in plant response to abiotic stress. Several members have been identified to be regulators for plants response to abscisic acid (ABA) signaling. Here, we isolated a subgroup I CDPK gene, ZmCPK4, from maize. Quantitative real time PCR (qRT-PCR) analysis revealed that the ZmCPK4 transcripts were induced by various stresses and signal molecules. Transient and stable expression of the ZmCPK4-GFP fusion proteins revealed ZmCPK4 localized to the membrane. Moreover, overexpression of ZmCPK4 in the transgenic Arabidopsis enhanced ABA sensitivity in seed germination, seedling growth and stomatal movement. The transgenic plants also enhanced drought stress tolerance. Taken together, the results suggest that ZmCPK4 might be involved in ABA-mediated regulation of stomatal closure in response to drought stress. PMID:23911729

  5. Hormonally regulated overexpression of Arabidopsis WUS and conifer LEC1 (CHAP3A) in transgenic white spruce: implications for somatic embryo development and somatic seedling growth.

    Science.gov (United States)

    Klimaszewska, Krystyna; Pelletier, Gervais; Overton, Catherine; Stewart, Don; Rutledge, Robert G

    2010-07-01

    Adult conifers are still recalcitrant in clonal propagation despite significant advances in forest tree biotechnology. Plant regeneration through somatic embryogenesis from explants older than mature zygotic embryos is either difficult or impossible to achieve. To investigate if ectopic expression of transcription factors involved in the induction of the embryogenic process would induce somatic embryogenesis in Picea glauca (white spruce) somatic plants, we used the LEAFY-COTYLEDON1 homolog cloned from Picea mariana, CHAP3A, and Arabidopsis thaliana WUS to transform embryonal mass of P. glauca. Ectopic gene expression was induced by 17-beta-estradiol during stages of somatic embryogenesis (early embryogenesis and late embryogenesis) and somatic seedling growth in the transgenics. Of the two transcription factors, only WUS produced severe phenotypes by disrupting the development of somatic embryos on the maturation medium and inhibiting germination. However, none of the transgenes induced ectopic somatic embryogenesis even in the presence of plant growth regulators. Absolute quantitative PCR confirmed the expression of both CHAP3A and WUS in transgenic embryonal mass and in all parts of somatic seedlings. A high expression of the transgenes did not influence expression profiles of any of the ten other transcription factors tested, some of which have been known to be involved in the process of embryogenesis. Implications of these results for further work are discussed. PMID:20424847

  6. Ectopic overexpression of SsCBF1, a CRT/DRE-binding factor from the nightshade plant Solanum lycopersicoides, confers freezing and salt tolerance in transgenic Arabidopsis.

    Directory of Open Access Journals (Sweden)

    Lili Zhang

    Full Text Available The C-repeat (CRT/dehydration-responsive element (DRE binding factor (CBF/DREB1 transcription factors play a key role in cold response. However, the detailed roles of many plant CBFs are far from fully understood. A CBF gene (SsCBF1 was isolated from the cold-hardy plant Solanum lycopersicoides. A subcellular localization study using GFP fusion protein indicated that SsCBF1 is localized in the nucleus. We delimited the SsCBF1 transcriptional activation domain to the C-terminal segment comprising amino acid residues 193-228 (SsCBF1(193-228. The expression of SsCBF1 could be dramatically induced by cold, drought and high salinity. Transactivation assays in tobacco leaves revealed that SsCBF1 could specifically bind to the CRT cis-elements in vivo to activate the expression of downstream reporter genes. The ectopic overexpression of SsCBF1 conferred increased freezing and high-salinity tolerance and late flowering phenotype to transgenic Arabidopsis. RNA-sequencing data exhibited that a set of cold and salt stress responsive genes were up-regulated in transgenic Arabidopsis. Our results suggest that SsCBF1 behaves as a typical CBF to contribute to plant freezing tolerance. Increased resistance to high-salinity and late flowering phenotype derived from SsCBF1 OE lines lend more credence to the hypothesis that plant CBFs participate in diverse physiological and biochemical processes related to adverse conditions.

  7. Expression of an alfalfa (Medicago sativa L.) peroxidase gene in transgenic Arabidopsis thaliana enhances resistance to NaCl and H2O2.

    Science.gov (United States)

    Teng, K; Xiao, G Z; Guo, W E; Yuan, J B; Li, J; Chao, Y H; Han, L B

    2016-01-01

    Peroxidases (PODs) are enzymes that play important roles in catalyzing the reduction of H2O2 and the oxidation of various substrates. They function in many different and important biological processes, such as defense mechanisms, immune responses, and pathogeny. The POD genes have been cloned and identified in many plants, but their function in alfalfa (Medicago sativa L.) is not known, to date. Based on the POD gene sequence (GenBank accession No. L36157.1), we cloned the POD gene in alfalfa, which was named MsPOD. MsPOD expression increased with increasing H2O2. The gene was expressed in all of the tissues, including the roots, stems, leaves, and flowers, particularly in stems and leaves under light/dark conditions. A subcellular analysis showed that MsPOD was localized outside the cells. Transgenic Arabidopsis with MsPOD exhibited increased resistance to H2O2 and NaCl. Moreover, POD activity in the transgenic plants was significantly higher than that in wild-type Arabidopsis. These results show that MsPOD plays an important role in resistance to H2O2 and NaCl. PMID:27323080

  8. A seed preferential heat shock transcription factor from wheat provides abiotic stress tolerance and yield enhancement in transgenic Arabidopsis under heat stress environment.

    Directory of Open Access Journals (Sweden)

    Harsh Chauhan

    Full Text Available Reduction in crop yield and quality due to various abiotic stresses is a worldwide phenomenon. In the present investigation, a heat shock factor (HSF gene expressing preferentially in developing seed tissues of wheat grown under high temperatures was cloned. This newly identified heat shock factor possesses the characteristic domains of class A type plant HSFs and shows high similarity to rice OsHsfA2d, hence named as TaHsfA2d. The transcription factor activity of TaHsfA2d was confirmed through transactivation assay in yeast. Transgenic Arabidopsis plants overexpressing TaHsfA2d not only possess higher tolerance towards high temperature but also showed considerable tolerance to salinity and drought stresses, they also showed higher yield and biomass accumulation under constant heat stress conditions. Analysis of putative target genes of AtHSFA2 through quantitative RT-PCR showed higher and constitutive expression of several abiotic stress responsive genes in transgenic Arabidopsis plants over-expressing TaHsfA2d. Under stress conditions, TaHsfA2d can also functionally complement the T-DNA insertion mutants of AtHsfA2, although partially. These observations suggest that TaHsfA2d may be useful in molecular breeding of crop plants, especially wheat, to improve yield under abiotic stress conditions.

  9. Biomonitoring of non-dioxin-like polychlorinated biphenyls in transgenic Arabidopsis using the mammalian pregnane X receptor system: a role of pectin in pollutant uptake.

    Directory of Open Access Journals (Sweden)

    Lieming Bao

    Full Text Available Polychlorinated biphenyls (PCBs are persistent organic pollutants damaging to human health and the environment. Techniques to indicate PCB contamination in planta are of great interest to phytoremediation. Monitoring of dioxin-like PCBs in transgenic plants carrying the mammalian aryl hydrocarbon receptor (AHR has been reported previously. Herein, we report the biomonitoring of non-dioxin-like PCBs (NDL-PCBs using the mammalian pregnane X receptor (PXR. In the transgenic Arabidopsis designated NDL-PCB Reporter, the EGFP-GUS reporter gene was driven by a promoter containing 18 repeats of the xenobiotic response elements, while PXR and its binding partner retinoid X receptor (RXR were coexpressed. Results showed that, in live cells, the expression of reporter gene was insensitive to endogenous lignans, carotenoids and flavonoids, but responded to all tested NDL-PCBs in a dose- and time- dependent manner. Two types of putative PCB metabolites, hydroxy- PCBs and methoxy- PCBs, displayed different activation properties. The vascular tissues seemed unable to transport NDL-PCBs, whereas mutation in QUASIMODO1 encoding a 1,4-galacturonosyltransferase led to reduced PCB accumulation in Arabidopsis, revealing a role for pectin in the control of PCB translocation. Taken together, the reporter system may serve as a useful tool to biomonitor the uptake and metabolism of NDL-PCBs in plants.

  10. A maize mitogen-activated protein kinase kinase, ZmMKK1, positively regulated the salt and drought tolerance in transgenic Arabidopsis.

    Science.gov (United States)

    Cai, Guohua; Wang, Guodong; Wang, Li; Liu, Yang; Pan, Jiaowen; Li, Dequan

    2014-07-15

    Mitogen-activated protein kinase (MAPK) cascades are highly conserved signal transduction modules in animals, plants and yeast. MAPK cascades are complicated networks and play vital roles in signal transduction pathways involved in biotic and abiotic stresses. In this study, a maize MAPKK gene, ZmMKK1, was characterized. Quantitative real time PCR (qRT-PCR) analysis demonstrated that ZmMKK1 transcripts were induced by diverse stresses and ABA signal molecule in maize root. Further study showed that the ZmMKK1-overexpressing Arabidopsis enhanced the tolerance to salt and drought stresses. However, seed germination, post-germination growth and stomatal aperture analysis demonstrated that ZmMKK1 overexpression was sensitive to ABA in transgenic Arabidopsis. Molecular genetic analysis revealed that the overexpression of ZmMKK1 in Arabidopsis enhanced the expression of ROS scavenging enzyme- and ABA-related genes, such as POD, CAT, RAB18 and RD29A under salt and drought conditions. In addition, heterologous overexpression of ZmMKK1 in yeast (Saccharomyces cerevisiae) improved the tolerance to salt and drought stresses. These results suggested that ZmMKK1 might act as an ABA- and ROS-dependent protein kinase in positive modulation of salt and drought tolerance. Most importantly, ZmMKK1 interacted with ZmMEKK1 as evidenced by yeast two-hybrid assay, redeeming a deficiency of MAPK interaction partners in maize. PMID:24974327

  11. An intergenic region shared by At4g35985 and At4g35987 in Arabidopsis thaliana is a tissue specific and stress inducible bidirectional promoter analyzed in transgenic arabidopsis and tobacco plants.

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    Joydeep Banerjee

    Full Text Available On chromosome 4 in the Arabidopsis genome, two neighboring genes (calmodulin methyl transferase At4g35987 and senescence associated gene At4g35985 are located in a head-to-head divergent orientation sharing a putative bidirectional promoter. This 1258 bp intergenic region contains a number of environmental stress responsive and tissue specific cis-regulatory elements. Transcript analysis of At4g35985 and At4g35987 genes by quantitative real time PCR showed tissue specific and stress inducible expression profiles. We tested the bidirectional promoter-function of the intergenic region shared by the divergent genes At4g35985 and At4g35987 using two reporter genes (GFP and GUS in both orientations in transient tobacco protoplast and Agro-infiltration assays, as well as in stably transformed transgenic Arabidopsis and tobacco plants. In transient assays with GFP and GUS reporter genes the At4g35985 promoter (P85 showed stronger expression (about 3.5 fold compared to the At4g35987 promoter (P87. The tissue specific as well as stress responsive functional nature of the bidirectional promoter was evaluated in independent transgenic Arabidopsis and tobacco lines. Expression of P85 activity was detected in the midrib of leaves, leaf trichomes, apical meristemic regions, throughout the root, lateral roots and flowers. The expression of P87 was observed in leaf-tip, hydathodes, apical meristem, root tips, emerging lateral root tips, root stele region and in floral tissues. The bidirectional promoter in both orientations shows differential up-regulation (2.5 to 3 fold under salt stress. Use of such regulatory elements of bidirectional promoters showing spatial and stress inducible promoter-functions in heterologous system might be an important tool for plant biotechnology and gene stacking applications.

  12. Overexpression of SrUGT85C2 from Stevia reduced growth and yield of transgenic Arabidopsis by influencing plastidial MEP pathway.

    Science.gov (United States)

    Guleria, Praveen; Masand, Shikha; Yadav, Sudesh Kumar

    2014-04-15

    The transcript expression of a gene SrUGT85C2 has been documented for direct relation with steviol glycoside content in Stevia plant. Steviol glycoside and gibberellin biosynthetic routes are divergent branches of methyl erythritol-4 phosphate (MEP) pathway. So, SrUGT85C2 might be an influencing gibberellin content. Hence in the present study, transgenic Arabidopsis thaliana overexpressing SrUGT85C2 cDNA from Stevia rebaudiana was developed to check its effect on gibberellin accumulation and related plant growth parameters. The developed transgenics showed a noteworthy decrease of 78-83% in GA3 content. Moreover, the transgenics showed a gibberellin deficient phenotype comprising stunted hypocotyl length, reduced shoot growth and a significant fall in relative water content. Transgenics also showed 17-37 and 64-76% reduction in chlorophyll a and chlorophyll b contents, respectively. Reduction in photosynthetic pigments could be responsible for the noticed significant decrease in plant biomass. Like steviol glycoside and gibberellin biosynthesis, chlorophyll biosynthesis also occurs from the precursors isopentenyl diphosphate (IPP) and dimethylallyl diphosphate (DMAPP) of MEP pathway in the plastids. The observed downregulated expression of genes encoding MEP pathway enzymes geranyl geranyl diphosphate synthase (GGDPS), copalyl diphosphate synthase (CDPS), kaurenoic acid oxidase (KAO), chlorophyll synthetase and chlorophyll a oxygenase in transgenics overexpressing SrUGT85C2 might be responsible for the reduction in gibberellins as well as chlorophyll. This study has documented for the first time the regulatory role of SrUGT85C2 in the biosynthesis of steviol glycoside, gibberellins and chlorophyll. PMID:24518812

  13. Characterization of a glutamine synthetase gene DvGS2 from Dunaliella viridis and biochemical identification of DvGS2-transgenic Arabidopsis thaliana.

    Science.gov (United States)

    Zhu, Chenguang; Fan, Qianlan; Wang, Wei; Shen, Chunlei; Meng, Xiangzong; Tang, Yuanping; Mei, Bing; Xu, Zhengkai; Song, Rentao

    2014-02-25

    The salt-tolerant green alga Dunaliella has remarkable capability to survive in some extreme environments such as nitrogen starvation, which makes Dunaliella be a proper model for mining novel genes on nitrogen uptake or assimilation. In this study, a glutamine synthetase (GS) gene DvGS2 with amino acid identity of 72% to other homologous GS proteins, was isolated and characterized from Dunaliella viridis. Phylogenetic comparison with other GSs revealed that DvGS2 occupied an independent phylogenetic position. Expressional analysis in D. viridis cells under nitrogen starvation confirmed that DvGS2 increased its mRNA level in 12h. Subcellular localization study and functional analysis in a GS-deficient Escherichia coli mutant proved that DvGS2 was a chloroplastic and functional GS enzyme. In order to investigate the potential application of DvGS2 in higher plants, the transgenic studies of DvGS2 in Arabidopsis thaliana were carried out. Results showed that the transgenic lines expressed the DvGS2 gene and demonstrated obviously enhanced root length (29%), fresh weight (40%-48% at two concentrations of nitrate supplies), stem length (21%), leaf size (39%) and silique number (44%) in contrast with the wild-type Arabidopsis. Furthermore, the transgenic lines had higher total nitrogen content (35%-43%), total GS activity (39%-45%) and soluble protein concentration (23%-24%) than the wild type. These results indicated that the overexpression of DvGS2 in A. thaliana resulted in higher biomass and the improvement of the host's nitrogen use efficiency. PMID:24334123

  14. Stamen abscission zone transcriptome profiling reveals new candidates for abscission control: enhanced retention of floral organs in transgenic plants overexpressing Arabidopsis ZINC FINGER PROTEIN2.

    Science.gov (United States)

    Cai, Suqin; Lashbrook, Coralie C

    2008-03-01

    Organ detachment requires cell separation within abscission zones (AZs). Physiological studies have established that ethylene and auxin contribute to cell separation control. Genetic analyses of abscission mutants have defined ethylene-independent detachment regulators. Functional genomic strategies leading to global understandings of abscission have awaited methods for isolating AZ cells of low abundance and very small size. Here, we couple laser capture microdissection of Arabidopsis thaliana stamen AZs and GeneChip profiling to reveal the AZ transcriptome responding to a developmental shedding cue. Analyses focus on 551 AZ genes (AZ(551)) regulated at the highest statistical significance (P Gene Ontology Consortium functional categories for cell wall modifying proteins, extracellular regulators, and nuclear-residing transcription factors. Promoter-beta-glucuronidase expression of one transcription factor candidate, ZINC FINGER PROTEIN2 (AtZFP2), was elevated in stamen, petal, and sepal AZs. Flower parts of transgenic lines overexpressing AtZFP2 exhibited asynchronous and delayed abscission. Abscission defects were accompanied by altered floral morphology limiting pollination and fertility. Hand-pollination restored transgenic fruit development but not the rapid abscission seen in wild-type plants, demonstrating that pollination does not assure normal rates of detachment. In wild-type stamen AZs, AtZFP2 is significantly up-regulated postanthesis. Phenotype data from transgene overexpression studies suggest that AtZFP2 participates in processes that directly or indirectly influence organ shed. PMID:18192438

  15. A R2R3-MYB transcription factor that is specifically expressed in cotton (Gossypium hirsutum) fibers affects secondary cell wall biosynthesis and deposition in transgenic Arabidopsis.

    Science.gov (United States)

    Sun, Xiang; Gong, Si-Ying; Nie, Xiao-Ying; Li, Yang; Li, Wen; Huang, Geng-Qing; Li, Xue-Bao

    2015-07-01

    Secondary cell wall (SCW) is an important industrial raw material for pulping, papermaking, construction, lumbering, textiles and potentially for biofuel production. The process of SCW thickening of cotton fibers lays down the cellulose that will constitute the bulk (up to 96%) of the fiber at maturity. In this study, a gene encoding a MYB-domain protein was identified in cotton (Gossypium hirsutum) and designated as GhMYBL1. Quantitative real-time polymerase chain reaction (RT-PCR) analysis revealed that GhMYBL1 was specifically expressed in cotton fibers at the stage of secondary wall deposition. Further analysis indicated that this protein is a R2R3-MYB transcription factor, and is targeted to the cell nucleus. Overexpression of GhMYBL1 in Arabidopsis affected the formation of SCW in the stem xylem of the transgenic plants. The enhanced SCW thickening also occurred in the interfascicular fibers, xylary fibers and vessels of the GhMYBL1-overexpression transgenic plants. The expression of secondary wall-associated genes, such as CesA4, CesA7, CesA8, PAL1, F5H and 4CL1, were upregulated, and consequently, cellulose and lignin biosynthesis were enhanced in the GhMYBL1 transgenic plants. These data suggested that GhMYBL1 may participate in modulating the process of secondary wall biosynthesis and deposition of cotton fibers. PMID:25534543

  16. T cell receptor (TCR-transgenic CD8 lymphocytes rendered insensitive to transforming growth factor beta (TGFβ signaling mediate superior tumor regression in an animal model of adoptive cell therapy

    Directory of Open Access Journals (Sweden)

    Quatromoni Jon G

    2012-06-01

    Full Text Available Abstract Tumor antigen-reactive T cells must enter into an immunosuppressive tumor microenvironment, continue to produce cytokine and deliver apoptotic death signals to affect tumor regression. Many tumors produce transforming growth factor beta (TGFβ, which inhibits T cell activation, proliferation and cytotoxicity. In a murine model of adoptive cell therapy, we demonstrate that transgenic Pmel-1 CD8 T cells, rendered insensitive to TGFβ by transduction with a TGFβ dominant negative receptor II (DN, were more effective in mediating regression of established B16 melanoma. Smaller numbers of DN Pmel-1 T cells effectively mediated tumor regression and retained the ability to produce interferon-γ in the tumor microenvironment. These results support efforts to incorporate this DN receptor in clinical trials of adoptive cell therapy for cancer.

  17. Overexpression of WsSGTL1 gene of Withania somnifera enhances salt tolerance, heat tolerance and cold acclimation ability in transgenic Arabidopsis plants.

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    Manoj K Mishra

    Full Text Available BACKGROUND: Sterol glycosyltrnasferases (SGT are enzymes that glycosylate sterols which play important role in plant adaptation to stress and are medicinally important in plants like Withania somnifera. The present study aims to find the role of WsSGTL1 which is a sterol glycosyltransferase from W. somnifera, in plant's adaptation to abiotic stress. METHODOLOGY: The WsSGTL1 gene was transformed in Arabidopsis thaliana through Agrobacterium mediated transformation, using the binary vector pBI121, by floral dip method. The phenotypic and physiological parameters like germination, root length, shoot weight, relative electrolyte conductivity, MDA content, SOD levels, relative electrolyte leakage and chlorophyll measurements were compared between transgenic and wild type Arabidopsis plants under different abiotic stresses--salt, heat and cold. Biochemical analysis was done by HPLC-TLC and radiolabelled enzyme assay. The promoter of the WsSGTL1 gene was cloned by using Genome Walker kit (Clontech, USA and the 3D structures were predicted by using Discovery Studio Ver. 2.5. RESULTS: The WsSGTL1 transgenic plants were confirmed to be single copy by Southern and homozygous by segregation analysis. As compared to WT, the transgenic plants showed better germination, salt tolerance, heat and cold tolerance. The level of the transgene WsSGTL1 was elevated in heat, cold and salt stress along with other marker genes such as HSP70, HSP90, RD29, SOS3 and LEA4-5. Biochemical analysis showed the formation of sterol glycosides and increase in enzyme activity. When the promoter of WsSGTL1 gene was cloned from W. somnifera and sequenced, it contained stress responsive elements. Bioinformatics analysis of the 3D structure of the WsSGTL1 protein showed functional similarity with sterol glycosyltransferase AtSGT of A. thaliana. CONCLUSIONS: Transformation of WsSGTL1 gene in A. thaliana conferred abiotic stress tolerance. The promoter of the gene in W.somnifera was found

  18. Over-expression of JcDGAT1 from Jatropha curcas increases seed oil levels and alters oil quality in transgenic Arabidopsis thaliana.

    Science.gov (United States)

    Misra, Aparna; Khan, Kasim; Niranjan, Abhishek; Nath, Pravendra; Sane, Vidhu A

    2013-12-01

    The increasing consumption of fossil fuels and petroleum products is leading to their rapid depletion and is a matter of concern around the globe. Substitutes of fossil fuels are required to sustain the pace of economic development. In this context, oil from the non food crops (biofuel) has shown potential to substitute fossil fuels. Jatropha curcas is an excellent shrub spread and naturalized across the globe. Its oil contains a high percentage of unsaturated fatty acids (about 78-84% of total fatty acid content) making the oil suitable for biodiesel production. Despite its high oil content, it has been poorly studied in terms of important enzymes/genes responsible for oil biosynthesis. Here, we describe the isolation of the full length cDNA clone of JcDGAT1, a key enzyme involved in oil biosynthesis, from J. curcas seeds and manipulation of oil content and composition in transgenic Arabidopsis plants by its expression. Transcript analysis of JcDGAT1 reveals a gradual increase from early seed development to its maturation. Homozygous transgenic Arabidopsis lines expressing JcDGAT1 both under CaMV35S promoter and a seed specific promoter show an enhanced level of total oil content (up by 30-41%) in seeds but do not show any phenotypic differences. In addition, our studies also show alterations in the oil composition through JcDGAT1 expression. While the levels of saturated FAs such as palmitate and stearate in the oil do not change, there is significant reproducible decrease in the levels of oleic acid and a concomitant increase in levels of linolenic acid both under the CaMV35S promoter as well as the seed specific promoter. Our studies thus confirm that DGAT is involved in flux control in oil biosynthesis and show that JcDGAT1 could be used specifically to manipulate and improve oil content and composition in plants. PMID:24125179

  19. Overexpression of SpCBL6, a calcineurin B-like protein of Stipa purpurea, enhanced cold tolerance and reduced drought tolerance in transgenic Arabidopsis.

    Science.gov (United States)

    Zhou, Yanli; Cheng, Ying; Yang, Yunqiang; Li, Xiong; Supriyo, Basak; Sun, Xudong; Yang, Yongping

    2016-09-01

    The purpose of the present study was to characterize SpCBL6 (GenBank accession number: KT780442) from Stipa purpurea and elucidate the function of this protein in abiotic stress. The full-length cDNA of SpCBL6 was isolated from S. purpurea by rapid amplification of cDNA ends methods. Laser confocal microscopy was used to analyze the subcellular localization of SpCBL6. The constructs of 35S:GFP-SpCBL6 was used to transform wild-type (WT) Arabidopsis plants (ecotype Columbia-0) with the floral dip method. Quantitative reverse-transcription PCR (qRT-PCR), water potential, photosynthetic efficiency (F v/F m), and ion leakage was performed to investigate the role of SpCBL6 in abiotic stress. The open reading frame of SpCBL6 contains 681 bp nucleotides and encodes a 227-amino acid polypeptide. Phylogenetic analysis indicated that SpCBL6 showed the highest similarity with rice OsCBL6. SpCBL6 transcripts were induced by freezing and drought treatments. Subcellular localization analysis showed that SpCBL6 was located in membrane of protoplast. Overexpression of SpCBL6 in Arabidopsis thaliana demonstrated that the transgenic plants were more tolerant to cold treatment, but less tolerant to drought, compared with the plants. qRT-PCR analysis showed that the drought stress marker genes were inhibited in transgenic plants, whereas the cold stress marker genes were enhanced. Further analysis showed that SpCBL6-overexpressing plants showed enhanced water potential, photosynthetic efficiency (F v/F m), and reduced ion leakage compared with the wild-type after cold treatment. Collectively, these results indicate that SpCBL6, a new member of the CBL gene family isolated from S. purpurea, enhances cold tolerance and reduces drought tolerance in plants. PMID:27393148

  20. Overexpression of Poplar PtrWRKY89 in Transgenic Arabidopsis Leads to a Reduction of Disease Resistance by Regulating Defense-Related Genes in Salicylate- and Jasmonate-Dependent Signaling.

    Science.gov (United States)

    Jiang, Yuanzhong; Guo, Li; Liu, Rui; Jiao, Bo; Zhao, Xin; Ling, Zhengyi; Luo, Keming

    2016-01-01

    The plant hormones jasmonic acid (JA) and salicylic acid (SA) play key roles in plant defenses against pathogens and several WRKY transcription factors have been shown to have a role in SA/JA crosstalk. In a previous study, overexpression of the poplar WRKY gene PtrWRKY89 enhanced resistance to pathogens in transgenic poplars. In this study, the promoter of PtrWRKY89 (ProPtrWRKY89) was isolated and used to drive GUS reporter gene. High GUS activity was observed in old leaves of transgenic Arabidopsis containing ProPtrWRKY89-GUS construct and GUS expression was extremely induced by SA solution and SA+MeJA mixture but not by MeJA treatment. Subcellular localization and transactivation assays showed that PtrWRKY89 acted as a transcription activator in the nucleus. Constitutive expression of PtrWRKY89 in Arabidopsis resulted in more susceptible to Pseudomonas syringae and Botrytis cinerea compared to wild-type plants. Quantitative real-time PCR (qRT-PCR) analysis confirmed that marker genes of SA and JA pathways were down-regulated in transgenic Arabidopsis after pathogen inoculations. Overall, our results indicated that PtrWRKY89 modulates a cross talk in resistance to P. syringe and B. cinerea by negatively regulating both SA and JA pathways in Arabidopsis. PMID:27019084

  1. Overexpression of Poplar PtrWRKY89 in Transgenic Arabidopsis Leads to a Reduction of Disease Resistance by Regulating Defense-Related Genes in Salicylate- and Jasmonate-Dependent Signaling

    Science.gov (United States)

    Liu, Rui; Jiao, Bo; Zhao, Xin; Ling, Zhengyi; Luo, Keming

    2016-01-01

    The plant hormones jasmonic acid (JA) and salicylic acid (SA) play key roles in plant defenses against pathogens and several WRKY transcription factors have been shown to have a role in SA/JA crosstalk. In a previous study, overexpression of the poplar WRKY gene PtrWRKY89 enhanced resistance to pathogens in transgenic poplars. In this study, the promoter of PtrWRKY89 (ProPtrWRKY89) was isolated and used to drive GUS reporter gene. High GUS activity was observed in old leaves of transgenic Arabidopsis containing ProPtrWRKY89-GUS construct and GUS expression was extremely induced by SA solution and SA+MeJA mixture but not by MeJA treatment. Subcellular localization and transactivation assays showed that PtrWRKY89 acted as a transcription activator in the nucleus. Constitutive expression of PtrWRKY89 in Arabidopsis resulted in more susceptible to Pseudomonas syringae and Botrytis cinerea compared to wild-type plants. Quantitative real-time PCR (qRT-PCR) analysis confirmed that marker genes of SA and JA pathways were down-regulated in transgenic Arabidopsis after pathogen inoculations. Overall, our results indicated that PtrWRKY89 modulates a cross talk in resistance to P. syringe and B. cinerea by negatively regulating both SA and JA pathways in Arabidopsis. PMID:27019084

  2. Improvement of copper tolerance of Arabidopsis by transgenic expression of an allene oxide cyclase gene, GhAOC1, in upland cotton (Gossypium hirsutum L.)

    Institute of Scientific and Technical Information of China (English)

    Yuange Wang; Huaihua Liu; Qingguo Xin

    2015-01-01

    Allene oxide cyclase (AOC, E 5.3.99.6) is an essential enzyme in the jasmonic acid (JA) biosynthetic pathway and mediates a wide range of adaptive responses. In this report, five AOC genes (GhAOC1–GhAOC5) were cloned from upland cotton (Gossypium hirsutum L.), sequenced, and characterized. Real-time PCR analysis indicated that the transcripts of GhAOCs were abundantly expressed in roots and less in fibers, and regulated in cotton plants under methyl jasmonate (MeJA) and CuCl2 stresses. To investigate the role of GhAOC under copper stress, transgenic Arabidopsis plants overexpressing cotton GhAOC1 under control of the Cauliflower mosaic virus 35S (CaMV 35S) promoter were generated. Compared to untransformed plants, GhAOC1-overexpressing Arabidopsis thaliana plants exhibited markedly higher survival rate, shoot fresh weight, shoot dry weight, and photosynthetic efficiency, and reduced cell membrane damage and lipid peroxidation under copper stress. This study provides the first evidence that GhAOC1 plays an important role in copper stress tolerance.

  3. Improvement of copper tolerance of Arabidopsis by transgenic expression of an allene oxide cyclase gene, GhAOC1, in upland cotton (Gossypium hirsutum L.

    Directory of Open Access Journals (Sweden)

    Yuange Wang

    2015-08-01

    Full Text Available Allene oxide cyclase (AOC, E 5.3.99.6 is an essential enzyme in the jasmonic acid (JA biosynthetic pathway and mediates a wide range of adaptive responses. In this report, five AOC genes (GhAOC1–GhAOC5 were cloned from upland cotton (Gossypium hirsutum L., sequenced, and characterized. Real-time PCR analysis indicated that the transcripts of GhAOCs were abundantly expressed in roots and less in fibers, and regulated in cotton plants under methyl jasmonate (MeJA and CuCl2 stresses. To investigate the role of GhAOC under copper stress, transgenic Arabidopsis plants overexpressing cotton GhAOC1 under control of the Cauliflower mosaic virus 35S (CaMV 35S promoter were generated. Compared to untransformed plants, GhAOC1-overexpressing Arabidopsis thaliana plants exhibited markedly higher survival rate, shoot fresh weight, shoot dry weight, and photosynthetic efficiency, and reduced cell membrane damage and lipid peroxidation under copper stress. This study provides the first evidence that GhAOC1 plays an important role in copper stress tolerance.

  4. Responses of transgenic Arabidopsis plants and recombinant yeast cells expressing a novel durum wheat manganese superoxide dismutase TdMnSOD to various abiotic stresses.

    Science.gov (United States)

    Kaouthar, Feki; Ameny, Farhat-Khemakhem; Yosra, Kamoun; Walid, Saibi; Ali, Gargouri; Faiçal, Brini

    2016-07-01

    In plant cells, the manganese superoxide dismutase (Mn-SOD) plays an elusive role in the response to oxidative stress. In this study, we describe the isolation and functional characterization of a novel Mn-SOD from durum wheat (Triticum turgidum L. subsp. Durum), named TdMnSOD. Molecular phylogeny analysis showed that the durum TdMnSOD exhibited high amino acids sequence identity with other Mn-SOD plants. The three-dimensional structure showed that TdMnSOD forms a homotetramer and each subunit is composed of a predominantly α-helical N-terminal domain and a mixed α/β C-terminal domain. TdMnSOD gene expression analysis showed that this gene was induced by various abiotic stresses in durum wheat. The expression of TdMnSOD enhances tolerance of the transformed yeast cells to salt, osmotic, cold and H2O2-induced oxidative stresses. Moreover, the analysis of TdMnSOD transgenic Arabidopsis plants subjected to different environmental stresses revealed low H2O2 and high proline levels as compared to the wild-type plants. Compared with the non-transformed plants, an increase in the total SOD and two other antioxidant enzyme activities including catalase (CAT) and peroxidases (POD) was observed in the three transgenic lines subjected to abiotic stress. Taken together, these data provide evidence for the involvement of durum wheat TdMnSOD in tolerance to multiple abiotic stresses in crop plants. PMID:27152457

  5. Constitutive expression of a salinity-induced wheat WRKY transcription factor enhances salinity and ionic stress tolerance in transgenic Arabidopsis thaliana

    Energy Technology Data Exchange (ETDEWEB)

    Qin, Yuxiang, E-mail: yuxiangqin@126.com [Department of Biotechnology, University of Jinan, Jinan 250022 (China); Tian, Yanchen [The Key Laboratory of Plant Cell Engineering and Germplasm Innovation, Ministry of Education, School of Life Science, Shandong University, Jinan 250100 (China); Han, Lu; Yang, Xinchao [Department of Biotechnology, University of Jinan, Jinan 250022 (China)

    2013-11-15

    Highlights: •A class II WRKY transcription factor, TaWRKY79 was isolated and characterized. •TaWRKY79 was induced by NaCl or abscisic acid. •843 bp regulatory segment was sufficient to respond to ABA or NaCl treatment. •TaWRKY79 enhanced salinity and ionic tolerance while reduced sensitivity to ABA. •TaWRKY79 increased salinity and ionic tolerance in an ABA-dependent pathway. -- Abstract: The isolation and characterization of TaWRKY79, a wheat class II WRKY transcription factor, is described. Its 1297 bp coding region includes a 987 bp long open reading frame. TaWRKY79 was induced by stressing seedlings with either NaCl or abscisic acid (ABA). When a fusion between an 843 bp segment upstream of the TaWRKY79 coding sequence and GUS was introduced into Arabidopsis thaliana, GUS staining indicated that this upstream segment captured the sequence(s) required to respond to ABA or NaCl treatment. When TaWRKY79 was constitutively expressed as a transgene in A. thaliana, the transgenic plants showed an improved capacity to extend their primary root in the presence of either 100 mM NaCl, 10 mM LiCl or 2 μM ABA. The inference was that TaWRKY79 enhanced the level of tolerance to both salinity and ionic stress, while reducing the level of sensitivity to ABA. The ABA-related genes ABA1, ABA2 ABI1 and ABI5 were all up-regulated in the TaWRKY79 transgenic plants, suggesting that the transcription factor operates in an ABA-dependent pathway.

  6. Constitutive expression of a salinity-induced wheat WRKY transcription factor enhances salinity and ionic stress tolerance in transgenic Arabidopsis thaliana

    International Nuclear Information System (INIS)

    Highlights: •A class II WRKY transcription factor, TaWRKY79 was isolated and characterized. •TaWRKY79 was induced by NaCl or abscisic acid. •843 bp regulatory segment was sufficient to respond to ABA or NaCl treatment. •TaWRKY79 enhanced salinity and ionic tolerance while reduced sensitivity to ABA. •TaWRKY79 increased salinity and ionic tolerance in an ABA-dependent pathway. -- Abstract: The isolation and characterization of TaWRKY79, a wheat class II WRKY transcription factor, is described. Its 1297 bp coding region includes a 987 bp long open reading frame. TaWRKY79 was induced by stressing seedlings with either NaCl or abscisic acid (ABA). When a fusion between an 843 bp segment upstream of the TaWRKY79 coding sequence and GUS was introduced into Arabidopsis thaliana, GUS staining indicated that this upstream segment captured the sequence(s) required to respond to ABA or NaCl treatment. When TaWRKY79 was constitutively expressed as a transgene in A. thaliana, the transgenic plants showed an improved capacity to extend their primary root in the presence of either 100 mM NaCl, 10 mM LiCl or 2 μM ABA. The inference was that TaWRKY79 enhanced the level of tolerance to both salinity and ionic stress, while reducing the level of sensitivity to ABA. The ABA-related genes ABA1, ABA2 ABI1 and ABI5 were all up-regulated in the TaWRKY79 transgenic plants, suggesting that the transcription factor operates in an ABA-dependent pathway

  7. TaNAC29, a NAC transcription factor from wheat, enhances salt and drought tolerance in transgenic Arabidopsis

    OpenAIRE

    Huang, Quanjun; Wang, Yan; Li, Bin; Chang, Junli; Chen, Mingjie; Li, Kexiu; Yang, Guangxiao; He, Guangyuan

    2015-01-01

    Background NAC (NAM, ATAF, and CUC) transcription factors play important roles in plant biological processes, including phytohormone homeostasis, plant development, and in responses to various environmental stresses. Methods TaNAC29 was introduced into Arabidopsis using the Agrobacterium tumefaciens-mediated floral dipping method. TaNAC29-overexpression plants were subjected to salt and drought stresses for examining gene functions. To investigate tolerant mechanisms involved in the salt and ...

  8. Expression of a yeast-derived invertase in the cell wall of tobacco and Arabidopsis plants leads to accumulation of carbohydrate and inhibition of photosynthesis and strongly influences growth and phenotype of transgenic tobacco plants.

    OpenAIRE

    von Schaewen, A; Stitt, M; Schmidt, R.; Sonnewald, U; Willmitzer, L

    1990-01-01

    Chimeric genes consisting of the coding sequence of the yeast invertase gene suc 2 and different N-terminal portions of the potato-derived vacuolar protein proteinase inhibitor II fused to the 35S CaMV promoter and the poly-A site of the octopine synthase gene were transferred into tobacco and Arabidopsis thaliana plants using Agrobacterium based systems. Regenerated transgenic plants display a 50- to 500-fold higher invertase activity compared to non-transformed control plants. This invertas...

  9. The Reaumuria trigyna leucoanthocyanidin dioxygenase (RtLDOX) gene complements anthocyanidin synthesis and increases the salt tolerance potential of a transgenic Arabidopsis LDOX mutant.

    Science.gov (United States)

    Zhang, Huirong; Du, Chao; Wang, Yan; Wang, Jia; Zheng, Linlin; Wang, Yingchun

    2016-09-01

    Reaumuria trigyna is a typical, native desert halophyte that grows under extreme conditions in Inner Mongolia. In a previous transcriptomic profiling analysis, flavonoid pathway-related genes in R. trigyna showed significant differences in transcript abundance under salt stress. Leucoanthocyanidin dioxygenase (LDOX, EC 1.14.11.19) is one of three dioxygenases in the flavonoid pathway that catalyzes the formation of anthocyanidins from leucoanthocyanidins. In this study, we cloned the full-length cDNA of R. trigyna LDOX (RtLDOX), and found RtLDOX recombinant protein was able to replace flavanone-3-hydroxylase (F3H, EC 1.14.11.9), another dioxygenase in the flavonoid pathway, to convert naringenin to dihydrokaempferol in vitro. R. trigyna LDOX can complement the Arabidopsis LDOX mutant transparent testa11 (tt11-11), which has reduced proanthocyanin (PA) and anthocyanin levels in seeds, to accumulate these two compounds. Thus, RtLDOX acts as a multifunctional dioxygenase to effect the synthesis of PA and anthocyanins and can perform F3H dioxygenase activities in the flavonoid biosynthesis pathway. The RtLDOX promoter harbored many cis-acting elements that might be recognized and bound by transcription factors related to stress response. RtLDOX expression was strongly increased under salt stress, and RtLDOX transgenic Arabidopsis mutant under NaCl stress accumulated the content of flavonoids leading to an increased antioxidant activities and plant biomass. These results suggest that RtLDOX as a multifunctional dioxygenase in flavonoid biosynthesis involves in enhancing plant response to NaCl stress. PMID:27219053

  10. VrDREB2A, a DREB-binding transcription factor from Vigna radiata, increased drought and high-salt tolerance in transgenic Arabidopsis thaliana.

    Science.gov (United States)

    Chen, Honglin; Liu, Liping; Wang, Lixia; Wang, Suhua; Cheng, Xuzhen

    2016-03-01

    Mung bean (Vigna radiata L.) is commonly grown in Asia as an important nutritional dry grain legume, as it can survive better in arid conditions than other crops. Abiotic stresses, such as drought and high-salt contents, negatively impact its growth and production. The dehydration-responsive element-binding protein 2 (DREB2) transcription factors play a significant role in the response to these stress stimuli via transcriptional regulation of downstream genes containing the cis-element dehydration-responsive element (DRE). However, the molecular mechanisms involved in the drought tolerance of this species remain elusive, with very few reported candidate genes. No DREB2 ortholog has been reported for mung bean, and the function of mung bean DREB2 is not clear. In this study, a novel VrDREB2A gene with conserved AP2 domains and transactivation ability was isolated from mung bean. A modified VrDREB2A protein lacking the putative negative regulatory domain encoded by nucleotides 394-543 was shown to be localized in the nucleus. Expression of the VrDREB2A gene was induced by drought, high salt concentrations and abscisic acid treatment. Furthermore, comparing with the wild type Arabidopsis, the overexpression of VrDREB2A activated the expression of downstream genes in transgenic Arabidopsis, resulting in enhanced tolerance to drought and high-salt stresses and no growth retardation. The results from this study indicate that VrDREB2A functions as an important transcriptional activator and may help increase the abiotic stress tolerance of the mung bean plant. PMID:26646381

  11. Arabidopsis DNA polymerase lambda mutant is mildly sensitive to DNA double strand breaks but defective in integration ofa transgene.

    Directory of Open Access Journals (Sweden)

    Tomoyuki eFurukawa

    2015-05-01

    Full Text Available The DNA double-strand break (DSB is a critical type of damage, and can be induced by both endogenous sources (e.g. errors of oxidative metabolism, transposable elements, programmed meiotic breaks, or perturbation of the DNA replication fork and exogenous sources (e.g. ionizing radiation or radiomimetic chemicals. Although higher plants, like mammals, are thought to preferentially repair DSBs via nonhomologous end joining (NHEJ, much remains unclear about plant DSB repair pathways. Our reverse genetic approach suggests that DNA polymerase λ is involved in DSB repair in Arabidopsis. The Arabidopsis T-DNA insertion mutant (atpolλ-1 displayed sensitivity to both gamma-irradiation and treatment with radiomimetic reagents, but not to other DNA damaging treatments. The atpolλ-1 mutant showed a moderate sensitivity to DSBs, while Arabidopsis Ku70 and DNA ligase 4 mutants (atku70-3 and atlig4-2, both of which play critical roles in NHEJ, exhibited a hypersensitivity to these treatments. The atpolλ-1/atlig4-2 double mutant exhibited a higher sensitivity to DSBs than each single mutant, but the atku70/atpolλ-1 showed similar sensitivity to the atku70-3 mutant. We showed that transcription of the DNA ligase 1, DNA ligase 6, and Wee1 genes was quickly induced by BLM in several NHEJ deficient mutants in contrast to wild-type. Finally, the T-DNA transformation efficiency dropped in NHEJ deficient mutants and the lowest transformation efficiency was scored in the atpolλ-1/atlig4-2 double mutant. These results imply that AtPolλ is involved in both DSB repair and DNA damage response pathway.

  12. A thaumatin-like protein of Ocimum basilicum confers tolerance to fungal pathogen and abiotic stress in transgenic Arabidopsis

    Science.gov (United States)

    Misra, Rajesh Chandra; Sandeep; Kamthan, Mohan; Kumar, Santosh; Ghosh, Sumit

    2016-01-01

    Plant often responds to fungal pathogens by expressing a group of proteins known as pathogenesis-related proteins (PRs). The expression of PR is mediated through pathogen-induced signal-transduction pathways that are fine-tuned by phytohormones such as methyl jasmonate (MeJA). Here, we report functional characterization of an Ocimum basilicum PR5 family member (ObTLP1) that was identified from a MeJA-responsive expression sequence tag collection. ObTLP1 encodes a 226 amino acid polypeptide that showed sequence and structural similarities with a sweet-tasting protein thaumatin of Thaumatococcus danielli and also with a stress-responsive protein osmotin of Nicotiana tabacum. The expression of ObTLP1 in O. basilicum was found to be organ-preferential under unstressed condition, and responsive to biotic and abiotic stresses, and multiple phytohormone elicitations. Bacterially-expressed recombinant ObTLP1 inhibited mycelial growth of the phytopathogenic fungi, Scleretonia sclerotiorum and Botrytis cinerea; thereby, suggesting its antifungal activity. Ectopic expression of ObTLP1 in Arabidopsis led to enhanced tolerance to S. sclerotiorum and B. cinerea infections, and also to dehydration and salt stress. Moreover, induced expression of the defense marker genes suggested up-regulation of the defense-response pathways in ObTLP1-expressing Arabidopsis upon fungal challenge. Thus, ObTLP1 might be useful for providing tolerance to the fungal pathogens and abiotic stresses in crops. PMID:27150014

  13. Characterization of a glutamine synthetase gene DvGS1 from Dunaliella viridis and investigation of the impact on expression of DvGS1 in transgenic Arabidopsis thaliana.

    Science.gov (United States)

    Zhu, Chenguang; Fan, Qianlan; Wang, Wei; Shen, Chunlei; Wang, Peipei; Meng, Xiangzong; Tang, Yuanping; Mei, Bing; Xu, Zhengkai; Song, Rentao

    2014-01-01

    A novel glutamine synthetase (GS) gene DvGS1 showing highest amino acid sequence identity of 78 % with the other homologous GS proteins from green algae, was isolated and characterized from Dunaliella viridis. Phylogenetic analysis revealed that DvGS1 occupied an independent phylogenetic position which was different with the GSs from higher plants, animals and microbes. Functional complement in E. coli mutant confirmed that the DvGS1 encoded functional GS enzyme. Real-time PCR analysis of DvGS1 in D. viridis cells under nitrogen starvation revealed that the mRNA level of DvGS1 was positively up-regulated in 12 h. The DvGS1 levels at the points of 12 and 24 h were separately twofold and fourfold of the level before nitrogen starvation. In order to investigate the potential application of DvGS1 in higher plants, the transgenic study of DvGS1 in Arabidopsis thaliana was carried out. Phenotype identification demonstrated that all three transgenic lines of T3 generation showed obviously enhanced root length (26 %), fresh weight (22-46 % at two concentrations of nitrate supplies), stem length (26 %), leaf size (29 %) and silique number (30 %) compared with the wild-type Arabidopsis. Biochemical analysis confirmed that all three transgenic lines had higher total nitrogen content, soluble protein concentration, total amino acid content and the leaf GS activity than the wild type plants. The free NH4 (+) and NO3 (-) concentration in fresh leaves of three transgenic lines were reduced by 17-26 % and 14-15 % separately (at two concentrations of nitrate supplies) compared with those of the wild types. All the results indicated that over-expression of DvGS1 in Arabidopsis significantly results in the improvement of growth phenotype and the host's nitrogen use efficiency. PMID:24307252

  14. A Novel Role for Banana MaASR in the Regulation of Flowering Time in Transgenic Arabidopsis.

    Science.gov (United States)

    Sun, Peiguang; Miao, Hongxia; Yu, Xiaomeng; Jia, Caihong; Liu, Juhua; Zhang, Jianbin; Wang, Jingyi; Wang, Zhuo; Wang, Anbang; Xu, Biyu; Jin, Zhiqiang

    2016-01-01

    The abscisic acid (ABA)-, stress-, and ripening-induced (ASR) protein is a plant-specific hydrophilic transcriptional factor involved in fruit ripening and the abiotic stress response. To date, there have been no studies on the role of ASR genes in delayed flowering time. Here, we found that the ASR from banana, designated as MaASR, was preferentially expressed in the banana female flowers from the eighth, fourth, and first cluster of the inflorescence. MaASR transgenic lines (L14 and L38) had a clear delayed-flowering phenotype. The number of rosette leaves, sepals, and pedicel trichomes in L14 and L38 was greater than in the wild type (WT) under long day (LD) conditions. The period of buds, mid-flowers, and full bloom of L14 and L38 appeared later than the WT. cDNA microarray and quantitative real-time PCR (qRT-PCR) analyses revealed that overexpression of MaASR delays flowering through reduced expression of several genes, including photoperiod pathway genes, vernalization pathway genes, gibberellic acid pathway genes, and floral integrator genes, under short days (SD) for 28 d (from vegetative to reproductive transition stage); however, the expression of the autonomous pathway genes was not affected. This study provides the first evidence of a role for ASR genes in delayed flowering time in plants. PMID:27486844

  15. A Novel Role for Banana MaASR in the Regulation of Flowering Time in Transgenic Arabidopsis

    Science.gov (United States)

    Yu, Xiaomeng; Jia, Caihong; Liu, Juhua; Zhang, Jianbin; Wang, Jingyi; Wang, Zhuo; Wang, Anbang; Xu, Biyu; Jin, Zhiqiang

    2016-01-01

    The abscisic acid (ABA)-, stress-, and ripening-induced (ASR) protein is a plant-specific hydrophilic transcriptional factor involved in fruit ripening and the abiotic stress response. To date, there have been no studies on the role of ASR genes in delayed flowering time. Here, we found that the ASR from banana, designated as MaASR, was preferentially expressed in the banana female flowers from the eighth, fourth, and first cluster of the inflorescence. MaASR transgenic lines (L14 and L38) had a clear delayed-flowering phenotype. The number of rosette leaves, sepals, and pedicel trichomes in L14 and L38 was greater than in the wild type (WT) under long day (LD) conditions. The period of buds, mid-flowers, and full bloom of L14 and L38 appeared later than the WT. cDNA microarray and quantitative real-time PCR (qRT-PCR) analyses revealed that overexpression of MaASR delays flowering through reduced expression of several genes, including photoperiod pathway genes, vernalization pathway genes, gibberellic acid pathway genes, and floral integrator genes, under short days (SD) for 28 d (from vegetative to reproductive transition stage); however, the expression of the autonomous pathway genes was not affected. This study provides the first evidence of a role for ASR genes in delayed flowering time in plants. PMID:27486844

  16. Practical Parallel Rendering

    CERN Document Server

    Chalmers, Alan

    2002-01-01

    Meeting the growing demands for speed and quality in rendering computer graphics images requires new techniques. Practical parallel rendering provides one of the most practical solutions. This book addresses the basic issues of rendering within a parallel or distributed computing environment, and considers the strengths and weaknesses of multiprocessor machines and networked render farms for graphics rendering. Case studies of working applications demonstrate, in detail, practical ways of dealing with complex issues involved in parallel processing.

  17. Fast projective volume rendering : approximating the rendering

    OpenAIRE

    Cignoni, Paolo; Montani, Claudio; Sarti, Donatella; Scopigno, Roberto

    1995-01-01

    How to render very complex datasets, and yet maintain interactive response times, is a hot topic in volume rendering. In this paper we focus on projective visualization of datasets represented via tetrahedral tessellations. Direct projective visualization is performed by sorting tetrahedra with respect to view direction and then by projecting them onto the screen. Different sorting algorythms and "per tetrahedra" projection techniques are reviewed and evaluated. anew method fot tetrahedra pro...

  18. Assays of polychlorinated biphenyl congeners and co-contaminated heavy metals in the transgenic Arabidopsis plants carrying the recombinant guinea pig aryl hydrocarbon receptor-mediated β-glucuronidase reporter gene expression system.

    Science.gov (United States)

    Shimazu, Sayuri; Ohta, Masaya; Ohkawa, Hideo; Ashida, Hitoshi

    2012-01-01

    The transgenic Arabidopsis plant XgD2V11-6 carrying the recombinant guinea pig (g) aryl hydrocarbon receptor (AhR)-mediated β-glucuronidase (GUS) reporter gene expression system was examined for assay of polychlorinated biphenyl (PCB) congeners and co-contaminated heavy metals. When the transgenic Arabidopsis plants were treated with PCB126 (toxic equivalency factor; TEF: 0.1) and PCB169 (TEF: 0.03), the GUS activity of the whole plants was increased significantly. After treatment with PCB80 (TEF: 0), the GUS activity was nearly the same level as that treated with 0.1% dimethylsulfoxide (DMSO) as a vehicle control. After exposure to a 1:1 mixture of PCB126 and PCB169, the GUS activity was increased additively. However, after exposure to a mixture of PCB126 and PCB80, the GUS activity was lower than that of the treatment with PCB126 alone. Thus, PCB80 seemed to be an antagonist towards AhR. When the transgenic plants were treated with each of the heavy metals Fe, Cu, Zn, Cd and Pb together with PCB126, Cd and Pb increased the PCB126-induced GUS activity. On the other hand, Fe, Cu and Zn did not affect the PCB126-induced GUS activity. In the presence of the biosurfactant mannosylerythritol lipid-B (MEL-B) and the carrier protein bovine serum albumin (BSA), the PCB126-induced GUS activity was increased, but the Cd-assisted PCB126-induced GUS activity was not affected. Thus, MEL-B and BSA seemed to increase uptake and transport of PCB126, respectively. PMID:22938576

  19. Harpin-induced expression and transgenic overexpression of the phloem protein gene AtPP2-A1 in Arabidopsis repress phloem feeding of the green peach aphid Myzus persicae

    Directory of Open Access Journals (Sweden)

    Sun Weiwei

    2011-01-01

    Full Text Available Abstract Background Treatment of plants with HrpNEa, a protein of harpin group produced by Gram-negative plant pathogenic bacteria, induces plant resistance to insect herbivores, including the green peach aphid Myzus persicae, a generalist phloem-feeding insect. Under attacks by phloem-feeding insects, plants defend themselves using the phloem-based defense mechanism, which is supposed to involve the phloem protein 2 (PP2, one of the most abundant proteins in the phloem sap. The purpose of this study was to obtain genetic evidence for the function of the Arabidopsis thaliana (Arabidopsis PP2-encoding gene AtPP2-A1 in resistance to M. persicae when the plant was treated with HrpNEa and after the plant was transformed with AtPP2-A1. Results The electrical penetration graph technique was used to visualize the phloem-feeding activities of apterous agamic M. persicae females on leaves of Arabidopsis plants treated with HrpNEa and an inactive protein control, respectively. A repression of phloem feeding was induced by HrpNEa in wild-type (WT Arabidopsis but not in atpp2-a1/E/142, the plant mutant that had a defect in the AtPP2-A1 gene, the most HrpNEa-responsive of 30 AtPP2 genes. In WT rather than atpp2-a1/E/142, the deterrent effect of HrpNEa treatment on the phloem-feeding activity accompanied an enhancement of AtPP2-A1 expression. In PP2OETAt (AtPP2-A1-overexpression transgenic Arabidopsis thaliana plants, abundant amounts of the AtPP2-A1 gene transcript were detected in different organs, including leaves, stems, calyces, and petals. All these organs had a deterrent effect on the phloem-feeding activity compared with the same organs of the transgenic control plant. When a large-scale aphid population was monitored for 24 hours, there was a significant decrease in the number of aphids that colonized leaves of HrpNEa-treated WT and PP2OETAt plants, respectively, compared with control plants. Conclusions The repression in phloem-feeding activities of

  20. Nonsymbiotic hemoglobin-2 leads to an elevated energy state and to a combined increase in polyunsaturated fatty acids and total oil content when overexpressed in developing seeds of transgenic Arabidopsis plants.

    Science.gov (United States)

    Vigeolas, Helene; Hühn, Daniela; Geigenberger, Peter

    2011-03-01

    Nonsymbiotic hemoglobins are ubiquitously expressed in plants and divided into two different classes based on gene expression pattern and oxygen-binding properties. Most of the published research has been on the function of class 1 hemoglobins. To investigate the role of class 2 hemoglobins, transgenic Arabidopsis (Arabidopsis thaliana) plants were generated overexpressing Arabidopsis hemoglobin-2 (AHb2) under the control of a seed-specific promoter. Overexpression of AHb2 led to a 40% increase in the total fatty acid content of developing and mature seeds in three subsequent generations. This was mainly due to an increase in the polyunsaturated C18:2 (ω-6) linoleic and C18:3 (ω-3) α-linolenic acids. Moreover, AHb2 overexpression led to an increase in the C18:2/C18:1 and C18:3/C18:2 ratios as well as in the C18:3 content in mol % of total fatty acids and in the unsaturation/saturation index of total seed lipids. The increase in fatty acid content was mainly due to a stimulation of the rate of triacylglycerol synthesis, which was attributable to a 3-fold higher energy state and a 2-fold higher sucrose content of the seeds. Under low external oxygen, AHb2 overexpression maintained an up to 5-fold higher energy state and prevented fermentation. This is consistent with AHb2 overexpression results in improved oxygen availability within developing seeds. In contrast to this, overexpression of class 1 hemoglobin did not lead to any significant increase in the metabolic performance of the seeds. These results provide evidence for a specific function of class 2 hemoglobin in seed oil production and in promoting the accumulation of polyunsaturated fatty acids by facilitating oxygen supply in developing seeds. PMID:21205621

  1. Overexpression of Two PsnAP1 Genes from Populus simonii × P. nigra Causes Early Flowering in Transgenic Tobacco and Arabidopsis

    OpenAIRE

    Zheng, Tangchun; Li, Shuang; Zang, Lina; Dai, Lijuan; Yang, Chuanping; Qu, Guan-Zheng

    2014-01-01

    In Arabidopsis, AP1 is a floral meristem identity gene and plays an important role in floral organ development. In this study, PsnAP1-1 and PsnAP1-2 were isolated from the male reproductive buds of poplar (Populus simonii × P. nigra), which are the orthologs of AP1 in Arabidopsis, by sequence analysis. Northern blot and qRT-PCR analysis showed that PsnAP1-1 and PsnAP1-2 exhibited high expression level in early inflorescence development of poplar. Subcellular localization showed the PsnAP1-1 a...

  2. Multivariate volume rendering

    Energy Technology Data Exchange (ETDEWEB)

    Crawfis, R.A.

    1996-03-01

    This paper presents a new technique for representing multivalued data sets defined on an integer lattice. It extends the state-of-the-art in volume rendering to include nonhomogeneous volume representations. That is, volume rendering of materials with very fine detail (e.g. translucent granite) within a voxel. Multivariate volume rendering is achieved by introducing controlled amounts of noise within the volume representation. Varying the local amount of noise within the volume is used to represent a separate scalar variable. The technique can also be used in image synthesis to create more realistic clouds and fog.

  3. Video-based rendering

    CERN Document Server

    Magnor, Marcus A

    2005-01-01

    Driven by consumer-market applications that enjoy steadily increasing economic importance, graphics hardware and rendering algorithms are a central focus of computer graphics research. Video-based rendering is an approach that aims to overcome the current bottleneck in the time-consuming modeling process and has applications in areas such as computer games, special effects, and interactive TV. This book offers an in-depth introduction to video-based rendering, a rapidly developing new interdisciplinary topic employing techniques from computer graphics, computer vision, and telecommunication en

  4. Field testing of transgenic cotton expressing Arabidopsis ABA INSENSITIVE5 and B3- domain related to ABI3/VIVIPAROUS1 (RAV) transcription factors.

    Science.gov (United States)

    We conducted field trials for ABI5 and RAV transgenics under the most extreme heat and drought conditions on record. The data validate greenhouse experiments that show AtRAV1 and AtRAV2 overexpression results in an average of 9% increases in fiber length without yield penalty and with greater gin t...

  5. Simultaneous Over-Expression of PaSOD and RaAPX in Transgenic Arabidopsis thaliana Confers Cold Stress Tolerance through Increase in Vascular Lignifications

    OpenAIRE

    Shafi, Amrina; Dogra, Vivek; Gill, Tejpal; Ahuja, Paramvir Singh; Sreenivasulu, Yelam

    2014-01-01

    Antioxidant enzymes play a significant role in eliminating toxic levels of reactive oxygen species (ROS), generated during stress from living cells. In the present study, two different antioxidant enzymes namely copper-zinc superoxide dismutase derived from Potentilla astrisanguinea (PaSOD) and ascorbate peroxidase (RaAPX) from Rheum austral both of which are high altitude cold niche area plants of Himalaya were cloned and simultaneously over-expressed in Arabidopsis thaliana to alleviate col...

  6. Functional characterization of various algal carotenoid ketolases reveals that ketolating zeaxanthin efficiently is essential for high production of astaxanthin in transgenic Arabidopsis

    OpenAIRE

    Zhong, Yu-Juan; Huang, Jun-Chao; Liu, Jin; Li, Yin; Jiang, Yue; Xu, Zeng-Fu; Sandmann, Gerhard; Chen, Feng

    2011-01-01

    Extending the carotenoid pathway to astaxanthin in plants is of scientific and industrial interest. However, expression of a microbial β-carotene ketolase (BKT) that catalyses the formation of ketocarotenoids in transgenic plants typically results in low levels of astaxanthin. The low efficiency of BKTs in ketolating zeaxanthin to astaxanthin is proposed to be the major limitation for astaxanthin accumulation in engineered plants. To verify this hypothesis, several algal BKTs were functionall...

  7. Characterization of Rice Homeobox Genes, OsHOX22 and OsHOX24, and Over-expression of OsHOX24 in Transgenic Arabidopsis Suggest their Role in Abiotic Stress Response

    Directory of Open Access Journals (Sweden)

    Annapurna eBhattacharjee

    2016-05-01

    Full Text Available Homeobox transcription factors are well known regulators of plant growth and development. In this study, we carried out functional analysis of two candidate stress-responsive HD-ZIP I class homeobox genes from rice, OsHOX22 and OsHOX24. These genes were highly upregulated under various abiotic stress conditions at different stages of rice development, including seedling, mature and reproductive stages. The transcript levels of these genes were enhanced significantly in the presence of plant hormones, including abscisic acid (ABA, auxin, salicylic acid and gibberellic acid. The recombinant full-length and truncated homeobox proteins were found to be localized in the nucleus. Electrophoretic mobility shift assay established the binding of these homeobox proteins with specific DNA sequences, AH1 (CAAT(A/TATTG and AH2 (CAAT(C/GATTG. Transactivation assays in yeast revealed the transcriptional activation potential of full-length OsHOX22 and OsHOX24 proteins. Homo- and hetero-dimerization capabilities of these proteins have also been demonstrated. Further, we identified putative novel interacting proteins of OsHOX22 and OsHOX24 via yeast-two hybrid analysis. Over-expression of OsHOX24 imparted higher sensitivity to stress hormone, ABA, and abiotic stresses in the transgenic Arabidopsis plants as revealed by various physiological and phenotypic assays. Microarray analysis revealed differential expression of several stress-responsive genes in transgenic lines as compared to wild-type. Many of these genes were found to be involved in transcriptional regulation and various metabolic pathways. Altogether, our results suggest the possible role of OsHOX22/OsHOX24 homeobox proteins as negative regulators in abiotic stress responses.

  8. Characterization of Rice Homeobox Genes, OsHOX22 and OsHOX24, and Over-expression of OsHOX24 in Transgenic Arabidopsis Suggest Their Role in Abiotic Stress Response.

    Science.gov (United States)

    Bhattacharjee, Annapurna; Khurana, Jitendra P; Jain, Mukesh

    2016-01-01

    Homeobox transcription factors are well known regulators of plant growth and development. In this study, we carried out functional analysis of two candidate stress-responsive HD-ZIP I class homeobox genes from rice, OsHOX22, and OsHOX24. These genes were highly up-regulated under various abiotic stress conditions at different stages of rice development, including seedling, mature and reproductive stages. The transcript levels of these genes were enhanced significantly in the presence of plant hormones, including abscisic acid (ABA), auxin, salicylic acid, and gibberellic acid. The recombinant full-length and truncated homeobox proteins were found to be localized in the nucleus. Electrophoretic mobility shift assay established the binding of these homeobox proteins with specific DNA sequences, AH1 (CAAT(A/T)ATTG) and AH2 (CAAT(C/G)ATTG). Transactivation assays in yeast revealed the transcriptional activation potential of full-length OsHOX22 and OsHOX24 proteins. Homo- and hetero-dimerization capabilities of these proteins have also been demonstrated. Further, we identified putative novel interacting proteins of OsHOX22 and OsHOX24 via yeast-two hybrid analysis. Over-expression of OsHOX24 imparted higher sensitivity to stress hormone, ABA, and abiotic stresses in the transgenic Arabidopsis plants as revealed by various physiological and phenotypic assays. Microarray analysis revealed differential expression of several stress-responsive genes in transgenic lines as compared to wild-type. Many of these genes were found to be involved in transcriptional regulation and various metabolic pathways. Altogether, our results suggest the possible role of OsHOX22/OsHOX24 homeobox proteins as negative regulators in abiotic stress responses. PMID:27242831

  9. Characterization of Rice Homeobox Genes, OsHOX22 and OsHOX24, and Over-expression of OsHOX24 in Transgenic Arabidopsis Suggest Their Role in Abiotic Stress Response

    Science.gov (United States)

    Bhattacharjee, Annapurna; Khurana, Jitendra P.; Jain, Mukesh

    2016-01-01

    Homeobox transcription factors are well known regulators of plant growth and development. In this study, we carried out functional analysis of two candidate stress-responsive HD-ZIP I class homeobox genes from rice, OsHOX22, and OsHOX24. These genes were highly up-regulated under various abiotic stress conditions at different stages of rice development, including seedling, mature and reproductive stages. The transcript levels of these genes were enhanced significantly in the presence of plant hormones, including abscisic acid (ABA), auxin, salicylic acid, and gibberellic acid. The recombinant full-length and truncated homeobox proteins were found to be localized in the nucleus. Electrophoretic mobility shift assay established the binding of these homeobox proteins with specific DNA sequences, AH1 (CAAT(A/T)ATTG) and AH2 (CAAT(C/G)ATTG). Transactivation assays in yeast revealed the transcriptional activation potential of full-length OsHOX22 and OsHOX24 proteins. Homo- and hetero-dimerization capabilities of these proteins have also been demonstrated. Further, we identified putative novel interacting proteins of OsHOX22 and OsHOX24 via yeast-two hybrid analysis. Over-expression of OsHOX24 imparted higher sensitivity to stress hormone, ABA, and abiotic stresses in the transgenic Arabidopsis plants as revealed by various physiological and phenotypic assays. Microarray analysis revealed differential expression of several stress-responsive genes in transgenic lines as compared to wild-type. Many of these genes were found to be involved in transcriptional regulation and various metabolic pathways. Altogether, our results suggest the possible role of OsHOX22/OsHOX24 homeobox proteins as negative regulators in abiotic stress responses. PMID:27242831

  10. Colour Rendering Index and colour rendering of LEDs

    OpenAIRE

    Dangol, Rajendra

    2011-01-01

    The purpose of this study was to understand CIE (Commission Internationale del Eclairage) Colour Rendering Index (CRI) and its deficiencies. Another aim was to find out limitation of CIE CRI for LEDs. Finally, current works on colour rendering of LEDs was examined in the study. CIE (Commission Internationale del Eclairage) Colour Rendering Index (CRI) is the only internationally recognized colour rendering metric. This metric expresses the colour rendering properties of light sources bas...

  11. Constitutive over-expression of rice ClpD1 protein enhances tolerance to salt and desiccation stresses in transgenic Arabidopsis plants.

    Science.gov (United States)

    Mishra, Ratnesh Chandra; Richa; Grover, Anil

    2016-09-01

    Caseinolytic proteases (Clps) perform the important role of removing protein aggregates from cells, which can otherwise prove to be highly toxic. ClpD system is a two-component protease complex composed of a regulatory ATPase module ClpD and a proteolytic component ClpP. Under desiccation stress condition, rice ClpD1 (OsClpD1) gene encoding for the regulatory subunit, was represented by four variant transcripts differing mainly in the expanse of their N-terminal amino acids. These transcripts were expressed in a differential manner in response to salt, mannitol and polyethylene glycol stresses in rice. Purified OsClpD1.3 protein exhibited intrinsic chaperone activity, shown using citrate synthase as substrate. Arabidopsis (Col-0) plants over-expressing OsClpD1.3 open reading frame downstream to CaMV35S promoter (ClpD1.3 plants) showed higher tolerance to salt and desiccation stresses as compared to wild type plants. ClpD1.3 seedlings also showed enhanced growth during the early stages of seed germination under unstressed, control conditions. The free proline levels and starch breakdown activities were higher in the ClpD1.3 seedlings as compared to the wild type Arabidopsis seedlings. It thus emerges that increasing the potential of ClpD1 chaperoning activity may be of advantage in protection against abiotic stresses. PMID:27457985

  12. BTF Rendering in Blender

    Czech Academy of Sciences Publication Activity Database

    Hatka, Martin; Haindl, Michal

    New York, USA: The Association for Computing Machinery, Inc, 2011, s. 265-272. ISBN 978-1-4503-1060-4. [International Conference on Virtual Reality Continuum and Its Applications in Industry 2011 /10./. Hong Kong (CN), 11.12.2011-12.12.2011] R&D Projects: GA MŠk 1M0572; GA ČR GAP103/11/0335; GA ČR GA102/08/0593 Grant ostatní: CESNET(CZ) 387/2010 Institutional research plan: CEZ:AV0Z10750506 Keywords : rendering * biderectional texture function * Blender Subject RIV: BD - Theory of Information http://library.utia.cas.cz/separaty/2012/RO/hatka-btf rendering in blender.pdf

  13. Over-expression of JcDREB, a putative AP2/EREBP domain-containing transcription factor gene in woody biodiesel plant Jatropha curcas, enhances salt and freezing tolerance in transgenic Arabidopsis thaliana.

    Science.gov (United States)

    Tang, Mingjuan; Liu, Xiaofei; Deng, Huaping; Shen, Shihua

    2011-12-01

    Jatropha curcas L. is an all-purpose biodiesel plant and is widely distributed in tropical and subtropical climates. It can grow well on poor quality soil which is not qualified for crop cultivation. This is very important for relieving land, food and energy crises. However, tropical and subtropical distribution limits the production of J. curcas seed. So it is valuable to know the molecular mechanism of J. curcas response to adverse abiotic environmental factors, especially freezing stress, in order to change the plant's characteristics. Until now there are just a few reports about J. curcas molecular biology. In this paper, we cloned and characterized a DNA binding protein from this plant, designated as JcDREB. Sequence analysis and yeast one-hybrid assays show that JcDREB can effectively function as a transcription factor of DREB protein family belonging to A-6 subgroup member. Expression patterns of JcDREB showed that it was induced by cold, salt and drought stresses, not by ABA. Over-expression of JcDREB in transgenic Arabidopsis exhibited enhanced salt and freezing stresses. Understanding the molecular mechanisms of J. curcas responses to environmental stresses, for example, high salinity, drought and low temperature, is crucial for improving their stress tolerance and productivity. This work provides more information about A-6 subgroup members of DREB subfamily. PMID:21958703

  14. Characterization of the Ubiquitin E2 Enzyme Variant Gene Family in Arabidopsis

    Institute of Scientific and Technical Information of China (English)

    Yu Zhang; Pei Wen; On-Sun Lau; Xing-Wang Deng

    2007-01-01

    Ubiquitin E2 enzyme variant (UEV) proteins are similar to ubiquitin-conjugating enzyme (E2) in both sequence and structure, but the lack of a catalytic cysteine residue renders them incapable of forming a thiolester linkage with ubiquitin. While the functional roles of several UEVs have been defined in yeast and animal systems, Arabidopsis COP10, a photomorphogenesis repressor, is the only UEV characterized in plants. Phylogenetic analysis revealed that the eight Arabidopsis UEV genes belong to three subfamilies.The expression of those genes is supported by either the presence of ESTs or RT-PCR analysis. We also characterized the other members of the COP10 subfamily, UEV2. Semi-quantitative RT-PCR analysis indicated that the UEV2 transcripts can be detected in most organs of Arabidopsis. Analysis of UEV2::GUS transgenic lines also showed its ubiquitous expression in nearly all the developmental stages of Arabidopsis.Transient expression analysis indicated that the sGFP-UEV2 fusion protein can localize to both the cytoplasm and nucleus. A T-DNA insertion mutant, uev2-1, which abolished the transcription of UEV2, displays no visible phenotype. Further, the cop10-4 uev2-1 double mutant exhibits the same phenotype as the cop10-4mutant in darkness. UEV2 is therefore not functionally redundant with COP10.

  15. A rice LSD1-like-type ZFP gene OsLOL5 enhances saline-alkaline tolerance in transgenic Arabidopsis thaliana, yeast and rice

    OpenAIRE

    Guan, QJ; Ma, HY; Wang, ZJ; Wang, ZY; Bu, QY; Liu, SK

    2016-01-01

    Background Zinc finger proteins (ZFPs) play an important role in regulating plant responses to abiotic stress. However, little is known about the function of LSD1-like-type ZFP in saline-alkaline (SA) stress resistance of rice. In this study, OsLOL5 (GenBank No. AJ620677), containing two LSD1-like-type C2C2 domains, was isolated and analyzed its protection roles in transgenic plants and yeast. OsLOL5 was located in the nucleus as evidenced by the bombardment of onion epidermal cells. Results ...

  16. Rendering the Topological Spines

    Energy Technology Data Exchange (ETDEWEB)

    Nieves-Rivera, D. [Lawrence Livermore National Lab. (LLNL), Livermore, CA (United States)

    2015-05-05

    Many tools to analyze and represent high dimensional data already exits yet most of them are not flexible, informative and intuitive enough to help the scientists make the corresponding analysis and predictions, understand the structure and complexity of scientific data, get a complete picture of it and explore a greater number of hypotheses. With this in mind, N-Dimensional Data Analysis and Visualization (ND²AV) is being developed to serve as an interactive visual analysis platform with the purpose of coupling together a number of these existing tools that range from statistics, machine learning, and data mining, with new techniques, in particular with new visualization approaches. My task is to create the rendering and implementation of a new concept called topological spines in order to extend ND²AV's scope. Other existing visualization tools create a representation preserving either the topological properties or the structural (geometric) ones because it is challenging to preserve them both simultaneously. Overcoming such challenge by creating a balance in between them, the topological spines are introduced as a new approach that aims to preserve them both. Its render using OpenGL and C++ and is currently being tested to further on be implemented on ND²AV. In this paper I will present what are the Topological Spines and how they are rendered.

  17. A GRAS-like gene of sunflower (Helianthus annuus L.) alters the gibberellin content and axillary meristem outgrowth in transgenic Arabidopsis plants.

    Science.gov (United States)

    Fambrini, M; Mariotti, L; Parlanti, S; Salvini, M; Pugliesi, C

    2015-11-01

    The GRAS proteins belong to a plant transcriptional regulator family that function in the regulation of plant growth and development. Despite their important roles, in sunflower only one GRAS gene (HaDella1) with the DELLA domain has been reported. Here, we provide a functional characterisation of a GRAS-like gene from Helianthus annuus (Ha-GRASL) lacking the DELLA motif. The Ha-GRASL gene contains an intronless open reading frame of 1,743 bp encoding 580 amino acids. Conserved motifs in the GRAS domain are detected, including VHIID, PFYRE, SAW and two LHR motifs. Within the VHII motif, the P-H-N-D-Q-L residues are entirely maintained. Phylogenetic analysis reveals that Ha-GRASL belongs to the SCARECROW LIKE4/7 (SCL4/7) subfamily of the GRAS consensus tree. Accumulation of Ha-GRASL mRNA at the adaxial boundaries from P6/P7 leaf primordia suggests a role of Ha-GRASL in the initiation of median and basal axillary meristems (AMs) of sunflower. When Ha-GRASL is over-expressed in Arabidopsis wild-type plants, the number of lateral bolts increases differently from untransformed plants. However, Ha-GRASL slightly affects the lateral suppressor (las-4-) mutation. Therefore, we hypothesise that Ha-GRASL and LAS are not functionally equivalent. The over-expression of Ha-GRASL reduces metabolic flow of gibberellins (GAs) in Arabidopsis and this modification could be relevant in AM development. Phylogenetic analysis includes LAS and SCL4/7 in the same major clade, suggesting a more recent separation of these genes with respect to other GRAS members. We propose that some features of their ancestor, as well as AM initiation and outgrowth, are partially retained in both LAS and SCL4/7. PMID:26081041

  18. High Fidelity Haptic Rendering

    CERN Document Server

    Otaduy, Miguel A

    2006-01-01

    The human haptic system, among all senses, provides unique and bidirectional communication between humans and their physical environment. Yet, to date, most human-computer interactive systems have focused primarily on the graphical rendering of visual information and, to a lesser extent, on the display of auditory information. Extending the frontier of visual computing, haptic interfaces, or force feedback devices, have the potential to increase the quality of human-computer interaction by accommodating the sense of touch. They provide an attractive augmentation to visual display and enhance t

  19. Three architectures for volume rendering

    OpenAIRE

    Hesser, Jürgen; Männer, Reinhard; Knittel, Günter; Straßer, Wolfgang; Pfister, Hanspeter; Kaufman, Arie

    1995-01-01

    Volume rendering is a key technique in scientific visualization that lends itself to significant exploitable parallelism. The high computational demands of real-time volume rendering and continued technological advances in the area of VLSI give impetus to the development of special-purpose volume rendering architectures. This paper presents and characterizes three recently developed volume rendering engines which are based on the ray-casting method. A taxonomy of the algorithmic variants of r...

  20. Vector quantization for volume rendering

    Science.gov (United States)

    Ning, Paul; Hesselink, Lambertus

    1992-01-01

    Volume rendering techniques typically process volumetric data in raw, uncompressed form. As algorithmic and architectural advances improve rendering speeds, however, larger data sets will be evaluated requiring consideration of data storage and transmission issues. In this paper, we analyze the data compression requirements for volume rendering applications and present a solution based on vector quantization. The proposed system compresses volumetric data and then renders images directly from the new data format. Tests on a fluid flow data set demonstrate that good image quality may be achieved at a compression ratio of 17:1 with only a 5 percent cost in additional rendering time.

  1. ARE: Ada Rendering Engine

    Directory of Open Access Journals (Sweden)

    Stefano Penge

    2009-10-01

    Full Text Available E' ormai pratica diffusa, nello sviluppo di applicazioni web, l'utilizzo di template e di potenti template engine per automatizzare la generazione dei contenuti da presentare all'utente. Tuttavia a volte la potenza di tali engine è€ ottenuta mescolando logica e interfaccia, introducendo linguaggi diversi da quelli di descrizione della pagina, o addirittura inventando nuovi linguaggi dedicati.ARE (ADA Rendering Engine è€ pensato per gestire l'intero flusso di creazione del contenuto HTML/XHTML dinamico, la selezione del corretto template, CSS, JavaScript e la produzione dell'output separando completamente logica e interfaccia. I templates utilizzati sono puro HTML senza parti in altri linguaggi, e possono quindi essere gestiti e visualizzati autonomamente. Il codice HTML generato è€ uniforme e parametrizzato.E' composto da due moduli, CORE (Common Output Rendering Engine e ALE (ADA Layout Engine.Il primo (CORE viene utilizzato per la generazione OO degli elementi del DOM ed è pensato per aiutare lo sviluppatore nella produzione di codice valido rispetto al DTD utilizzato. CORE genera automaticamente gli elementi del DOM in base al DTD impostato nella configurazioneIl secondo (ALE viene utilizzato come template engine per selezionare automaticamente in base ad alcuni parametri (modulo, profilo utente, tipologia del nodo, del corso, preferenze di installazione il template HTML, i CSS e i file JavaScript appropriati. ALE permette di usare templates di default e microtemplates ricorsivi per semplificare il lavoro del grafico.I due moduli possono in ogni caso essere utilizzati indipendentemente l'uno dall'altro. E' possibile generare e renderizzare una pagina HTML utilizzando solo CORE oppure inviare gli oggetti CORE al template engine ALE che provvede a renderizzare la pagina HTML. Viceversa è possibile generare HTML senza utilizzare CORE ed inviarlo al template engine ALECORE è alla prima release ed è€ già utilizzato all

  2. 拟南芥转or基因突变体转录组及表型分析%TRANSCRIPTOME AND PHENOTYPE ANALYSES OF or GENE TRANSGENIC ARABIDOPSIS MUTANT

    Institute of Scientific and Technical Information of China (English)

    门潇; 孙天虎; 杨永华

    2012-01-01

    构建了拟南芥orange(or)过表达突变体和相应的对照组,通过比较它们在色素含量、转录组、表型等方面的变化,发现or在绿色组织(拟南芥叶子、茎等)中也能起到提高类胡萝卜素含量的作用,且突变体类胡萝卜素合成途径的基因转录水平没有显著变化,但是很多防卫胁迫相关基因转录水平上调,说明突变体中存在胁迫环境.对不同生长条件下突变体幼苗下胚轴的测量等表明or突变体对光尤其是蓝光变得十分敏感.本研究分析比较了or在不同组织中的效应,为or应用于改良作物类胡萝卜素含量的基因工程和进一步揭示or的作用机制提供了参考.%It is known that orange(or) gene mutation leads to increased carotenoids content in plants.To elucidate the detailed mechanisms involved,Arabidopsis plants with over-expressed or and vector-only control were generated.Pigment content,transcriptome profile and mutant phenotypes were investigated.It was found that or was functional in green tissues,such as leaves and stems,although less functional than in non-green tissues.No major changes in transcription pattern were found for genes involved in carotenoids biosynthesis,but resistance-related genes,such as ZAT,were up-regulated,implying stressed environment in or mutants.Hypocotyl length measurements under different light conditions suggested that the or mutant became sensitive to light especially to blue light.Carotenoids enhancement of or in different plant tissues was analyzed,providing a reference for genetic engineering using or to improve nutritional status of crops,and for future work to uncover or regulatory mechanisms.

  3. Exposure Render: An Interactive Photo-Realistic Volume Rendering Framework

    OpenAIRE

    Kroes, T.; Post, F.H.; Botha, C.P.

    2012-01-01

    The field of volume visualization has undergone rapid development during the past years, both due to advances in suitable computing hardware and due to the increasing availability of large volume datasets. Recent work has focused on increasing the visual realism in Direct Volume Rendering (DVR) by integrating a number of visually plausible but often effect-specific rendering techniques, for instance modeling of light occlusion and depth of field. Besides yielding more attractive renderings, e...

  4. Parallel hierarchical radiosity rendering

    Energy Technology Data Exchange (ETDEWEB)

    Carter, M.

    1993-07-01

    In this dissertation, the step-by-step development of a scalable parallel hierarchical radiosity renderer is documented. First, a new look is taken at the traditional radiosity equation, and a new form is presented in which the matrix of linear system coefficients is transformed into a symmetric matrix, thereby simplifying the problem and enabling a new solution technique to be applied. Next, the state-of-the-art hierarchical radiosity methods are examined for their suitability to parallel implementation, and scalability. Significant enhancements are also discovered which both improve their theoretical foundations and improve the images they generate. The resultant hierarchical radiosity algorithm is then examined for sources of parallelism, and for an architectural mapping. Several architectural mappings are discussed. A few key algorithmic changes are suggested during the process of making the algorithm parallel. Next, the performance, efficiency, and scalability of the algorithm are analyzed. The dissertation closes with a discussion of several ideas which have the potential to further enhance the hierarchical radiosity method, or provide an entirely new forum for the application of hierarchical methods.

  5. The physics of volume rendering

    OpenAIRE

    Peters, Thomas

    2014-01-01

    Radiation transfer is an important topic in several physical disciplines, probably most prominently in astrophysics. Computer scientists use radiation transfer, among other things, for the visualization of complex data sets with direct volume rendering. In this article, I point out the connection between physical radiation transfer and volume rendering, and I describe an implementation of direct volume rendering in the astrophysical radiation transfer code RADMC-3D. I show examples for the us...

  6. The physics of volume rendering

    Science.gov (United States)

    Peters, Thomas

    2014-11-01

    Radiation transfer is an important topic in several physical disciplines, probably most prominently in astrophysics. Computer scientists use radiation transfer, among other things, for the visualization of complex data sets with direct volume rendering. In this article, I point out the connection between physical radiation transfer and volume rendering, and I describe an implementation of direct volume rendering in the astrophysical radiation transfer code RADMC-3D. I show examples for the use of this module on analytical models and simulation data.

  7. The physics of volume rendering

    CERN Document Server

    Peters, Thomas

    2014-01-01

    Radiation transfer is an important topic in several physical disciplines, probably most prominently in astrophysics. Computer scientists use radiation transfer, among other things, for the visualisation of complex data sets with direct volume rendering. In this note, I point out the connection between physical radiation transfer and volume rendering, and I describe an implementation of direct volume rendering in the astrophysical radiation transfer code RADMC-3D. I show examples for the use of this module on analytical models and simulation data.

  8. Interactive High Performance Volume Rendering

    OpenAIRE

    Zellmann, Stefan

    2014-01-01

    This thesis is about Direct Volume Rendering on high performance computing systems. As direct rendering methods do not create a lower-dimensional geometric representation, the whole scientific dataset must be kept in memory. Thus, this family of algorithms has a tremendous resource demand. Direct Volume Rendering algorithms in general are well suited to be implemented for dedicated graphics hardware. Nevertheless, high performance computing systems often do not provide resources for hardwa...

  9. A bacterial haloalkane dehalogenase gene as a negative selectable marker in Arabidopsis

    DEFF Research Database (Denmark)

    Næsted, Henrik; Fennema, M.; Hao, L.;

    1999-01-01

    , including Arabidopsis, tobacco, oil seed rape and rice, do not express detectable haloalkane dehalogenase activities, and that wild-type Arabidopsis grows in the presence of DCE. In contrast, DCE applied as a volatile can be used to select on plates or in soil transgenic Arabidopsis which express dhl...

  10. Time-Critical Volume Rendering

    Science.gov (United States)

    Kaufman, Arie

    1998-01-01

    For the past twelve months, we have conducted and completed a joint research entitled "Time- Critical Volume Rendering" with NASA Ames. As expected, High performance volume rendering algorithms have been developed by exploring some new faster rendering techniques, including object presence acceleration, parallel processing, and hierarchical level-of-detail representation. Using our new techniques, initial experiments have achieved real-time rendering rates of more than 10 frames per second of various 3D data sets with highest resolution. A couple of joint papers and technique reports as well as an interactive real-time demo have been compiled as the result of this project.

  11. Transgen kunst

    DEFF Research Database (Denmark)

    2007-01-01

    Oversættelse af kunstneren Eduardo Kac' tekst "Transgenic Art" i Passepartout #27. Interfacekulturens æstetik. Udgivelsesdato: 28.04.07......Oversættelse af kunstneren Eduardo Kac' tekst "Transgenic Art" i Passepartout #27. Interfacekulturens æstetik. Udgivelsesdato: 28.04.07...

  12. Topology-controlled volume rendering

    OpenAIRE

    Weber, Gunther H.; Dillard, Scott E.; Carr, Hamish; Pascucci, Valerio; Hamann, Bernd

    2007-01-01

    Topology provides a foundation for the development of mathematically sound tools for processing and exploration of scalar fields. Existing topology-based methods can be used to identify interesting features in volumetric data sets, to find seed sets for accelerated isosurface extraction, or to treat individual connected components as distinct entities for isosurfacing or interval volume rendering. We describe a framework for direct volume rendering based on segmenting ...

  13. Large fused GPU volume rendering

    OpenAIRE

    Lindholm, Stefan

    2008-01-01

    This master thesis describes the underlying theory and implementation of a fused GPU volume rendering pipeline. The open source framework of XIP, largely developed at Siemens Corporate Research, is extended with fusion capabilities through a Binary Space Partitioning approach. Regions in the intersection pattern of multiple volumes are identified and subsequently rendered using either Texture Slicing or Raycasting in a cell based fashion. Results demonstrate interactive frame rates for reason...

  14. Evidence for a disease-resistance pathway in rice similar to the NPR1-mediated signaling pathway in Arabidopsis.

    OpenAIRE

    Chern, M S; Fitzgerald, H A; YADAV, R. C.; Canlas, P E; Dong, X.; Ronald, P. C.

    2001-01-01

    The Arabidopsis NPR1/NIM1 gene is a key regulator of systemic acquired resistance (SAR). Over-expression of NPR1 leads to enhanced resistance in Arabidopsis. To investigate the role of NPR1 in monocots, we over-expressed the Arabidopsis NPR1 in rice and challenged the transgenic plants with Xanthomonas oryzae pv. oryzae (Xoo), the rice bacterial blight pathogen. The transgenic plants displayed enhanced resistance to Xoo. RNA blot hybridization indicates that enhanced resistance requires expre...

  15. 结缕草CBF基因的同源克隆及其转基因拟南芥的抗寒性验证%Cloning of Zoysiagrass CBF Gene and Validation of Cold Tolerance in Trans-genic Arabidopsis

    Institute of Scientific and Technical Information of China (English)

    冯勋伟; 才宏伟

    2014-01-01

    结缕草是优良的暖季型草坪草之一,主要用于亚热带和热带地区的草坪种植。抗冷性是结缕草栽培范围的限制因子。本研究以日本最北部原产的结缕草品系为材料,根据其他植物的已知的抗寒基因 CBF 序列,通过同源克隆的方法获得结缕草中相对应的同源基因ZjCBF;根据和其他已报告的CBF序列的比对结果,确定ZjCBF基因属于CBF转录因子家族基因中CBF1型基因。利用半定量PCR和实时定量PCR分析该基因在寒冷条件下的表达情况,发现ZjCBF基因受冷胁迫的诱导,在4℃处理6 h时表达量最高。在此基础上,本研究构建了该基因的过表达载体,并将其转化到拟南芥中,通过低温冷处理实验发现,不论是否经过冷驯化,转 ZjCBF 基因植株由于 ZjCBF 的过量表达均比野生型植株抗寒性强。%Zoysiagrass is recognized as an excellent warm-season turfgrass and mainly used in subtropical and tropical regions. Cold stress is a major constraint factor for the cultivation of zoysiagrass. In this study, according to the sequences of cold tolerance gene CBF had been reported in other plant species, we cloned the corresponding homologous of the ZjCBF gene by homology cloning method in Zoysia japonica using a material originated from the most northern area of Japan. Based on the alignment re-sults compared with other reported CBF genes, we found the ZjCBF gene belongs to the CBF1 familiy. By semi-quantitative PCR and real-time quantitative PCR, we analyzed the expression level of the ZjCBF gene in the cold condition and found that ZjCBF was induced by cold stress, and the ZjCBF expression reached peak at six hours post 4°C treatment. In addition, we also con-structed ZjCBF over expression vector and generated transgenic Arabidopsis plants, with better cold tolerance than the wild-type, whether through cold acclimation or not.

  16. Transgenic expression of Lactoferrin imparts resistance to a soilborne fungal pathogen Rhizoctonia solani

    Science.gov (United States)

    Transgenic tobacco (Nicotiana tabacum var Xanthi) and Arabidopsis (A. thaliana) plants expressing an antimicrobial bovine lactoferrin (BLF) gene were developed and evaluated for resistance against an economically important fungal pathogen Rhizoctonia solani, the causal agent of damping off diseases....

  17. Remote rendering for ultrascale data

    International Nuclear Information System (INIS)

    The mission of the SciDAC Institute for Ultrascale Visualization is to address the upcoming petascale visualization challenges. As we move to petascale computation, we are seeing a trend not only in the growth but also in the consolidation of computing resources. As the distances between user and petascale visualization resources grow, the expected performance of the network degrades, especially with respect to latency. In this paper we will explore a technique for remote visualization that leverages unstructured lumigraph rendering. This technique will provide an interactive rendering experience regardless of the network performance to the remote visualization resource. The unstructured lumigraph rendering can also replace many of the other level-of-detail techniques currently used that have problems that are exasperated by petascale data

  18. Advanced Material Rendering in Blender

    Czech Academy of Sciences Publication Activity Database

    Hatka, Martin; Haindl, Michal

    2012-01-01

    Roč. 11, č. 2 (2012), s. 15-23. ISSN 1081-1451 R&D Projects: GA ČR GAP103/11/0335; GA ČR GA102/08/0593 Grant ostatní: CESNET(CZ) 387/2010; CESNET(CZ) 409/2011 Institutional support: RVO:67985556 Keywords : realistic material rendering * bidirectional texture function * Blender Subject RIV: BD - Theory of Information http://library.utia.cas.cz/separaty/2013/RO/haindl-advanced material rendering in blender.pdf

  19. Transgenic Animals.

    Science.gov (United States)

    Jaenisch, Rudolf

    1988-01-01

    Describes three methods and their advantages and disadvantages for introducing genes into animals. Discusses the predictability and tissue-specificity of the injected genes. Outlines the applications of transgenic technology for studying gene expression, the early stages of mammalian development, mutations, and the molecular nature of chromosomes.…

  20. Illustrative rendering of vortex cores

    Czech Academy of Sciences Publication Activity Database

    Shafii, S.; Obermaier, H.; Kolář, Václav; Hlawitschka, M.; Garth, C.; Hamann, B.; Joy, K. I.

    Leipzig: The Eurographics Association, 2013 - (Hlawitschka, M.; Weinkauf, T.) [Eurographics Conference on Visualization (EuroVis 2013). Leipzig (DE), 17.06.2013-21.06.2013] Institutional support: RVO:67985874 Keywords : flow visualization * vortices * illustrative rendering Subject RIV: BK - Fluid Dynamics http://graphics.cs.ucdavis.edu/~hamann/ShafiiObermaierKolarHlawitschkaGarthHamannJoyEurovis2013ShortPaperAsPublished06172013.pdf

  1. Super resolution volume rendering hardware

    OpenAIRE

    Bosma, Marco; Smit, Jaap; Terwisscha van Scheltinga, Jeroen

    1995-01-01

    The resolution obtained in volume rendering is greatly increased over known methods through the introduction of super resolution techniques which make it possible to enlarge the view o f the dataset without the introduction of unnecessary positional, gradient and opacity errors. In this paper our "Super Resolution" technique will be introduced along with a corresponding hardware design.

  2. Rendering methods for augmented reality

    OpenAIRE

    Fischer, Jan

    2006-01-01

    Augmented reality (AR) has become a promising and fast-growing application of computer graphics over the course of the last years. Augmented reality systems overlay computer-generated graphical information over the view of the real world. Several main research challenges can be identified in the field of augmented reality. These are the design of advanced display devices (e.g., head-mounted displays), camera tracking, system design, user interaction, and rendering. While a major part of the p...

  3. Transgenic evaluation of activated mutant alleles of SOS2 reveals a critical requirement for its kinase activity and C-terminal regulatory domain for salt tolerance in Arabidopsis thaliana

    Science.gov (United States)

    Zhu, Jian-Kang; Quintero-Toscano, Francisco Javier; Pardo-Prieto, Jose Manuel; Qiu, Quansheng; Schumaker, Karen Sue; Ohta, Masaru; Zhang, Changqing; Guo, Yan

    2007-09-04

    The present invention provides a method of increasing salt tolerance in a plant by overexpressing a gene encoding a mutant SOS2 protein in at least one cell type in the plant. The present invention also provides for transgenic plants expressing the mutant SOS2 proteins.

  4. Genome-wide variation of the somatic mutation frequency in transgenic plants

    OpenAIRE

    Kovalchuk, Igor; Kovalchuk, Olga; Hohn, Barbara

    2000-01-01

    In order to analyse the frequency of point mutations in whole plants, several constructs containing single nonsense mutations in the β-glucuronidase (uidA) gene were used to generate transgenic Arabidopsis thaliana plants. Upon histochemical staining of transgenic plants, sectors indicative of transgene reactivation appeared. Reversion frequencies were in the range of 10–7–10–8 events per base pair, exceeding the previous estimates for other eukaryotes at least 100-fold. The frequency was dep...

  5. Characterization of a Maize Wip1 Promoter in Transgenic Plants

    Directory of Open Access Journals (Sweden)

    Shengxue Zhang

    2013-12-01

    Full Text Available The Maize Wip1 gene encodes a wound-induced Bowman-Birk inhibitor (BBI protein which is a type of serine protease inhibitor, and its expression is induced by wounding or infection, conferring resistance against pathogens and pests. In this study, the maize Wip1 promoter was isolated and its function was analyzed. Different truncated Wip1 promoters were fused upstream of the GUS reporter gene and transformed into Arabidopsis, tobacco and rice plants. We found that (1 several truncated maize Wip1 promoters led to strong GUS activities in both transgenic Arabidopsis and tobacco leaves, whereas low GUS activity was detected in transgenic rice leaves; (2 the Wip1 promoter was not wound-induced in transgenic tobacco leaves, but was induced by wounding in transgenic rice leaves; (3 the truncated Wip1 promoter had different activity in different organs of transgenic tobacco plants; (4 the transgenic plant leaves containing different truncated Wip1 promoters had low GUS transcripts, even though high GUS protein level and GUS activities were observed; (5 there was one transcription start site of Wip1 gene in maize and two transcription start sites of GUS in Wip1::GUS transgenic lines; (6 the adjacent 35S promoter which is present in the transformation vectors enhanced the activity of the truncated Wip1 promoters in transgenic tobacco leaves, but did not influence the disability of truncated Wip1231 promoter to respond to wounding signals. We speculate that an ACAAAA hexamer, several CAA trimers and several elements similar to ACAATTAC octamer in the 5'-untranslated region might contribute to the strong GUS activity in Wip1231 transgenic lines, meanwhile, compared to the 5'-untranslated region from Wip1231 transgenic lines, the additional upstream open reading frames (uORFs in the 5'-untranslated region from Wip1737 transgenic lines might contribute to the lower level of GUS transcript and GUS activity.

  6. GPU Pro advanced rendering techniques

    CERN Document Server

    Engel, Wolfgang

    2010-01-01

    This book covers essential tools and techniques for programming the graphics processing unit. Brought to you by Wolfgang Engel and the same team of editors who made the ShaderX series a success, this volume covers advanced rendering techniques, engine design, GPGPU techniques, related mathematical techniques, and game postmortems. A special emphasis is placed on handheld programming to account for the increased importance of graphics on mobile devices, especially the iPhone and iPod touch.Example programs and source code can be downloaded from the book's CRC Press web page. 

  7. Ray coherence in parallel volume rendering

    OpenAIRE

    Moloney, Brendan

    2008-01-01

    Ray coherence, meaning all processing along each ray is local to a single machine, is achieved in our parallel volume rendering environment by using a workload distribution scheme that divides the image space. This allows one to avoid the compositing stage when performing standard volume rendering in a parallel rendering pipeline. More importantly, there are a number of existing algorithms for volume rendering that either benefit from or require ray coherence when being adapted to a parallel ...

  8. Architectures for Real-Time Volume Rendering

    OpenAIRE

    Pfister, Hanspeter

    1999-01-01

    Over the last decade, volume rendering has become an invaluable visualization technique for a wide variety of applications. This paper reviews three special-purpose architectures for interactive volume rendering: texture mapping, VIRIM, and VolumePro. Commercial implementations of these architectures are available or underway. The discussion of each architecture will focus on the algorithm, system architecture, memory system, and volume rendering performance.

  9. Hardware Accelerated Point Rendering of Isosurfaces

    DEFF Research Database (Denmark)

    Bærentzen, Jakob Andreas; Christensen, Niels Jørgen

    2003-01-01

    advantage of rendering points as opposed to triangles increases with the size and complexity of the volumes. To gauge the visual quality of future hardware accelerated point rendering schemes, we have implemented a software based point rendering method and compare the quality to both MC and our OpenGL based...

  10. Real-time graphics rendering engine

    CERN Document Server

    Bao, Hujun

    2011-01-01

    ""Real-Time Graphics Rendering Engine"" reveals the software architecture of the modern real-time 3D graphics rendering engine and the relevant technologies based on the authors' experience developing this high-performance, real-time system. The relevant knowledge about real-time graphics rendering such as the rendering pipeline, the visual appearance and shading and lighting models are also introduced. This book is intended to offer well-founded guidance for researchers and developers who are interested in building their own rendering engines. Hujun Bao is a professor at the State Key Lab of

  11. Overexpression of lycopene ε-cyclase gene from lycium chinense confers tolerance to chilling stress in Arabidopsis thaliana.

    Science.gov (United States)

    Song, Xinyu; Diao, Jinjin; Ji, Jing; Wang, Gang; Li, Zhaodi; Wu, Jiang; Josine, Tchouopou Lontchi; Wang, Yurong

    2016-01-15

    Lutein plays an important role in protecting the photosynthetic apparatus from photodamage and eliminating ROS to render normal physiological function of cells. As a rate-limiting step for lutein synthesis in plants, lycopene ε-cyclase catalyzes lycopene to δ-carotene. We cloned a lycopene ε-cyclase gene (Lcε-LYC) from Lycium chinense (L. chinense), a deciduous woody perennial halophyte growing in various environmental conditions. The Lcε-LYC gene has an ORF of 1569bp encoding a protein of 522 aa. The deduced amino acid sequence of Lcε-LYC gene has higher homology with LycEs in other plants, such as Nicotiana tabacum and Solanum tuberosum. When L. chinense was exposed to chilling stress, relative expression of Lcε-LYC increased. To study the protective role of Lcε-LYC against chilling stress, we overexpressed the Lcε-LYC gene in Arabidopsis thaliana. Lcε-LYC overexpression led to an increase of lutein accumulation in transgenic A. thaliana, and the content of lutein decreased when transgenics were under cold conditions. In addition, the transgenic plants under chilling stress displayed higher activities of superoxide dismutase (SOD) and peroxidase (POD) and less H2O2 and malondialdehyde (MDA) than the control. Moreover, the photosynthesis rate, photosystem II activity (Fv/fm), and Non-photochemical quenching (NPQ) also increased in the transgenetic plants. On the whole, overexpression of Lcε-LYC ameliorates photoinhibition and photooxidation, and decreases the sensitivity of photosynthesis to chilling stress in transgenic plants. PMID:26526130

  12. Translational control of Arabidopsis meristem stability and organogenesis by the eukaryotic translation factor eIF3h.

    Directory of Open Access Journals (Sweden)

    Fujun Zhou

    Full Text Available Essentially all aboveground plant tissues develop from the stem cells in the primary shoot apical meristem. Proliferation of the stem cell population in the Arabidopsis shoot apical meristem is tightly controlled by a feedback loop formed primarily by the homeodomain transcription factor WUSCHEL (WUS and the CLAVATA ligand-receptor system. In this study, it is shown that mutation of a translation initiation factor, eIF3h, causes a tendency to develop a strikingly enlarged shoot apical meristem with elevated and ectopic expression of WUS and CLAVATA3 (CLV3. Many of the mRNAs that function in apical meristem maintenance possess upstream open reading frames (uORFs, translational attenuators that render translation partially dependent on eIF3h. Specifically, the mRNA for the receptor kinase, CLV1, is undertranslated in the eif3h mutant as shown by transient and transgenic expression assays. Concordant phenotypic observations include defects in organ polarity and in translation of another uORF-containing mRNA, ASYMMETRIC LEAVES 1 (AS1, in eif3h. In summary, the expression of developmental regulatory mRNAs is attenuated by uORFs, and this attenuation is balanced in part by the translation initiation factor, eIF3h. Thus, translational control plays a key role in Arabidopsis stem cell regulation and organogenesis.

  13. An Overview of Rendering from Volume Data --- including Surface and Volume Rendering

    OpenAIRE

    Jonathan C. Roberts

    1993-01-01

    Volume rendering is a title often ambiguously used in science. One meaning often quoted is: `to render any three volume dimensional data set'; however, within this categorisation `surface rendering'' is contained. Surface rendering is a technique for visualising a geometric representation of a surface from a three dimensional volume data set. A more correct definition of Volume Rendering would only incorporate the direct visualisation of volumes, without the use of intermediate surface geomet...

  14. Arabidopsis VQ motif-containing proteins VQ12 and VQ29 negatively modulate basal defense against Botrytis cinerea.

    Science.gov (United States)

    Wang, Houping; Hu, Yanru; Pan, Jinjing; Yu, Diqiu

    2015-01-01

    Arabidopsis VQ motif-containing proteins have recently been demonstrated to interact with several WRKY transcription factors; however, their specific biological functions and the molecular mechanisms underlying their involvement in defense responses remain largely unclear. Here, we showed that two VQ genes, VQ12 and VQ29, were highly responsive to the necrotrophic fungal pathogen Botrytis cinerea. To characterize their roles in plant defense, we generated amiR-vq12 transgenic plants by using an artificial miRNA approach to suppress the expression of VQ12, and isolated a loss-of-function mutant of VQ29. Phenotypic analysis showed that decreasing the expression of VQ12 and VQ29 simultaneously rendered the amiR-vq12 vq29 double mutant plants resistant against B. cinerea. Consistently, the B. cinerea-induced expression of defense-related PLANT DEFENSIN1.2 (PDF1.2) was increased in amiR-vq12 vq29. In contrast, constitutively-expressing VQ12 or VQ29 confered transgenic plants susceptible to B. cinerea. Further investigation revealed that VQ12 and VQ29 physically interacted with themselves and each other to form homodimers and heterodimer. Moreover, expression analysis of VQ12 and VQ29 in defense-signaling mutants suggested that they were partially involved in jasmonate (JA)-signaling pathway. Taken together, our study indicates that VQ12 and VQ29 negatively regulate plant basal resistance against B. cinerea. PMID:26394921

  15. ProteinShader: illustrative rendering of macromolecules

    OpenAIRE

    Weber Joseph R

    2009-01-01

    Abstract Background Cartoon-style illustrative renderings of proteins can help clarify structural features that are obscured by space filling or balls and sticks style models, and recent advances in programmable graphics cards offer many new opportunities for improving illustrative renderings. Results The ProteinShader program, a new tool for macromolecular visualization, uses information from Protein Data Bank files to produce illustrative renderings of proteins that approximate what an arti...

  16. Image Based Rendering under Varying Illumination

    Institute of Scientific and Technical Information of China (English)

    Wang Chengfeng (王城峰); Hu Zhanyi

    2003-01-01

    A new approach for photorealistic rendering of a class of objects at arbitrary illumination is presented. The approach of the authors relies entirely on image based rendering techniques. A scheme is utilized for re-illumination of objects based on linear combination of low dimensional image representations. The minimum rendering condition of technique of the authors is three sample images under varying illumination of a reference object and a single input image of an interested object. Important properties of this approach are its simplicity, robustness and speediness. Experimental results validate the proposed rendering approach.

  17. Direct Volume Rendering of Curvilinear Volumes

    Science.gov (United States)

    Vaziri, Arsi; Wilhelms, J.; Challinger, J.; Alper, N.; Ramamoorthy, S.; Kutler, Paul (Technical Monitor)

    1998-01-01

    Direct volume rendering can visualize sampled 3D scalar data as a continuous medium, or extract features. However, it is generally slow. Furthermore, most algorithms for direct volume rendering have assumed rectilinear gridded data. This paper discusses methods for using direct volume rendering when the original volume is curvilinear, i.e. is divided into six-sided cells which are not necessarily equilateral hexahedra. One approach is to ray-cast such volumes directly. An alternative approach is to interpolate the sample volumes to a rectilinear grid, and use this regular volume for rendering. Advantages and disadvantages of the two approaches in terms of speed and image quality are explored.

  18. Human GLTP and mutant forms of ACD11 suppress cell death in the Arabidopsis acd11 mutant

    DEFF Research Database (Denmark)

    Petersen, Nikolaj H T; McKinney, Lea V; Pike, Helen;

    2008-01-01

    The Arabidopsis acd11 mutant exhibits runaway, programmed cell death due to the loss of a putative sphingosine transfer protein (ACD11) with homology to mammalian GLTP. We demonstrate that transgenic expression in Arabidopsis thaliana of human GLTP partially suppressed the phenotype of the acd11 ...

  19. Bioavailability of nanoparticulate hematite to Arabidopsis thaliana

    International Nuclear Information System (INIS)

    The environmental effects and bioavailability of nanoparticulate iron (Fe) to plants are currently unknown. Here, plant bioavailability of synthesized hematite Fe nanoparticles was evaluated using Arabidopsis thaliana (A. thaliana) as a model. Over 56-days of growing wild-type A. thaliana, the nanoparticle-Fe and no-Fe treatments had lower plant biomass, lower chlorophyll concentrations, and lower internal Fe concentrations than the Fe-treatment. Results for the no-Fe and nanoparticle-Fe treatments were consistently similar throughout the experiment. These results suggest that nanoparticles (mean diameter 40.9 nm, range 22.3–67.0 nm) were not taken up and therefore not bioavailable to A. thaliana. Over 14-days growing wild-type and transgenic (Type I/II proton pump overexpression) A. thaliana, the Type I plant grew more than the wild-type in the nanoparticle-Fe treatment, suggesting Type I plants cope better with Fe limitation; however, the nanoparticle-Fe and no-Fe treatments had similar growth for all plant types. -- Highlights: ► Iron nanoparticles were synthesized and assessed for bioavailability to Arabidopsis. ► Arabidopsis grew better in the presence of EDTA-bound iron than nanoparticulate iron. ► Arabidopsis grew the same in the presence of nanoparticulate iron compared to no iron. -- Synthesized iron nanoparticles were not bioavailable to Arabidopsis thaliana in agar nutrient media

  20. Image Based Rendering and Virtual Reality

    DEFF Research Database (Denmark)

    Livatino, Salvatore

    The Presentation concerns with an overview of Image Based Rendering approaches and their use on Virtual Reality, including Virtual Photography and Cinematography, and Mobile Robot Navigation.......The Presentation concerns with an overview of Image Based Rendering approaches and their use on Virtual Reality, including Virtual Photography and Cinematography, and Mobile Robot Navigation....

  1. Physically based rendering from theory to implementation

    CERN Document Server

    Pharr, Matt

    2010-01-01

    "Physically Based Rendering, 2nd Edition" describes both the mathematical theory behind a modern photorealistic rendering system as well as its practical implementation. A method - known as 'literate programming'- combines human-readable documentation and source code into a single reference that is specifically designed to aid comprehension. The result is a stunning achievement in graphics education. Through the ideas and software in this book, you will learn to design and employ a full-featured rendering system for creating stunning imagery. This book features new sections on subsurface scattering, Metropolis light transport, precomputed light transport, multispectral rendering, and much more. It includes a companion site complete with source code for the rendering system described in the book, with support for Windows, OS X, and Linux. Code and text are tightly woven together through a unique indexing feature that lists each function, variable, and method on the page that they are first described.

  2. Moisture movements in render on brick wall

    DEFF Research Database (Denmark)

    Hansen, Kurt Kielsgaard; Munch, Thomas Astrup; Thorsen, Peter Schjørmann; Villumsen, Casper Rosengaard; Bentzon, Lars Chr.

    2003-01-01

    A three-layer render on brick wall used for building facades is studied in the laboratory. The vertical render surface is held in contact with water for 24 hours simulating driving rain while it is measured with non-destructive X-ray equipment every hour in order to follow the moisture front...... through the render and into the brick. The test specimen is placed between the source and the detector. The test specimens are all scanned before they are exposed to water. In that way the loss of counts from the dry scan to the wet scan qualitatively shows the presence of water. The results show nearly...... no penetration of water through the render and into the brick, and the results are independent of the start condition of the test specimens. Also drying experiments are performed. The results show a small difference in the rate of drying, in favour of the bricks without render....

  3. Neuroanatomy and transgenic technologies

    Science.gov (United States)

    This is a short review that introduces recent advances of neuroanatomy and transgenic technologies. The anatomical complexity of the nervous system remains a subject of tremendous fascination among neuroscientists. In order to tackle this extraordinary complexity, powerful transgenic technologies a...

  4. Visibility-Aware Direct Volume Rendering

    Institute of Scientific and Technical Information of China (English)

    Wai-Ho Mak; Yingcai Wu; Ming-Yuen Chan; Huamin Qu

    2011-01-01

    Direct volume rendering (DVR) is a powerful visualization technique which allows users to effectively explore and study volumetric datasets. Different transparency settings can be flexibly assigned to different structures such that some valuable information can be revealed in direct volume rendered images (DVRIs). However, end-users often feel that some risks are always associated with DVR because they do not know whether any important information is missing from the transparent regions of DVRIs. In this paper, we investigate how to semi-automatically generate a set of DVRIs and also an animation which can reveal information missed in the original DVRIs and meanwhile satisfy some image quality criteria such as coherence. A complete framework is developed to tackle various problems related to the generation and quality evaluation of visibility-aware DVRIs and animations. Our technique can reduce the risk of using direct volume rendering and thus boost the confidence of users in volume rendering systems.

  5. ARC Code TI: SLAB Spatial Audio Renderer

    Data.gov (United States)

    National Aeronautics and Space Administration — SLAB is a software-based, real-time virtual acoustic environment rendering system being developed as a tool for the study of spatial hearing. SLAB is designed to...

  6. A hybrid rendering algorithm for textile objects

    Institute of Scientific and Technical Information of China (English)

    ZHANG MingMin; PAN ZhiGeng; SHI JiaoYing; WANG Peng; MI QingFeng

    2009-01-01

    Although realistic texile rendering has been widely used in virtual garment and try-on systems,a robust method to simulate textile with a realistic appearance and high fidelity Is yet to be established.We propose to use a novel hybrid geometric-and image-based rendering (GIBR) method to achieve photo realistic representation of textile products.The image-based technique,with its radiance synthesis algorithm,enables us to recover the reflectance properties of textile in an environment photo,and thus can render the appearance of textile material.The geometry-based technique,with its traditional illumination model of assigning illumination parameters extracted from the original scene (such as radiance and chroma dispatch),makes it possible to interactively manipulate 3D virtual objects in the "real" environment.Our realistic textile rendering method has advantages over the traditional ones in its easiness to implement and its wide range of applications.

  7. Composed Scattering Model for Direct Volume Rendering

    Institute of Scientific and Technical Information of China (English)

    蔡文立; 石教英

    1996-01-01

    Based on the equation of transfer in transport theory of optical physics,a new volume rendering model,called composed scattering model(CSM),is presented.In calculating the scattering term of the equation,it is decomposed into volume scattering intensity and surface scattering intensity,and they are composed with the boundary detection operator as the weight function.This proposed model differs from the most current volume rendering models in the aspect that in CSM segmentation and illumination intensity calculation are taken as two coherent parts while in existing models they are regarded as two separate ones.This model has been applied to the direct volume rendering of 3D data sets obtained by CT and MRI.The resultant images show not only rich details but also clear boundary surfaces.CSM is demonstrated to be an accurate volume rendering model suitable for CT and MRI data sets.

  8. Implementing a Photorealistic Rendering System using GLSL

    OpenAIRE

    Hachisuka, Toshiya

    2015-01-01

    Ray tracing on GPUs is becoming quite common these days. There are many publicly available documents on how to implement basic ray tracing on GPUs for spheres and implicit surfaces. We even have some general frameworks for ray tracing on GPUs. We however hardly find details on how to implement more complex ray tracing algorithms themselves that are commonly used for photorealistic rendering. This paper explains an implementation of a stand-alone rendering system on GPUs which supports the bou...

  9. Fast Volume Rendering and Deformation Algorithms

    OpenAIRE

    Chen, Haixin

    2001-01-01

    Volume rendering is a technique for simultaneous visualization of surfaces and inner structures of objects. However, the huge number of volume primitives (voxels) in a volume, leads to high computational cost. In this dissertation I developed two algorithms for the acceleration of volume rendering and volume deformation. The first algorithm accelerates the ray casting of volume. Previous ray casting acceleration techniques like space-leaping and early-ray-termination are only efficient when m...

  10. Foundations for Measuring Volume Rendering Quality

    Science.gov (United States)

    Williams, Peter L.; Uselton, Samuel P.; Chancellor, Marisa K. (Technical Monitor)

    1997-01-01

    The goal of this paper is to provide a foundation for objectively comparing volume rendered images. The key elements of the foundation are: (1) a rigorous specification of all the parameters that need to be specified to define the conditions under which a volume rendered image is generated; (2) a methodology for difference classification, including a suite of functions or metrics to quantify and classify the difference between two volume rendered images that will support an analysis of the relative importance of particular differences. The results of this method can be used to study the changes caused by modifying particular parameter values, to compare and quantify changes between images of similar data sets rendered in the same way, and even to detect errors in the design, implementation or modification of a volume rendering system. If one has a benchmark image, for example one created by a high accuracy volume rendering system, the method can be used to evaluate the accuracy of a given image.

  11. Real Time Rendering of Deformable and Semi-Transparent Objects by Volume Rendering

    OpenAIRE

    Guetat, Amel

    2008-01-01

    Volume rendering is one of the key technique to display data from diverse application fields like medicine, industrial quality control, and numerical simulations in an appropriate way. The current main limitations are still the inadequate rendering speed and the limited flexibility of the most efficient algorithms. In this dissertation, we developed three new algorithms for the acceleration of direct volume rendering and volume deformation. The first algorithm consists on a first step, on the...

  12. Rendering and Compositing Infrastructure Improvements to VisIt for Insitu Rendering

    Energy Technology Data Exchange (ETDEWEB)

    Loring, Burlen [Lawrence Berkeley National Lab. (LBNL), Berkeley, CA (United States); Ruebel, Oliver [Lawrence Berkeley National Lab. (LBNL), Berkeley, CA (United States)

    2016-01-28

    Compared to posthoc rendering, insitu rendering often generates larger numbers of images, as a result rendering performance and scalability are critical in the insitu setting. In this work we present improvements to VisIt's rendering and compositing infrastructure that deliver increased performance and scalability in both posthoc and insitu settings. We added the capability for alpha blend compositing and use it with ordered compositing when datasets have disjoint block domain decomposition to optimize the rendering of transparent geometry. We also made improvements that increase overall efficiency by reducing communication and data movement and have addressed a number of performance issues. We structured our code to take advantage of SIMD parallelization and use threads to overlap communication and compositing. We tested our improvements on a 20 core workstation using 8 cores to render geometry generated from a $256^3$ cosmology dataset and on a Cray XC31 using 512 cores to render geometry generated from a $2000^2 \\times 800$ plasma dataset. Our results show that ordered compositing provides a speed up of up to $4 \\times$ over the current sort first strategy. The other improvements resulted in modest speed up with one notable exception where we achieve up to $40 \\times$ speed up of rendering and compositing of opaque geometry when both opaque and transparent geometry are rendered together. We also investigated the use of depth peeling, but found that the implementation provided by VTK is substantially slower,both with and without GPU acceleration, than a local camera order sort.

  13. Standardized rendering from IR surveillance motion imagery

    Science.gov (United States)

    Prokoski, F. J.

    2014-06-01

    Government agencies, including defense and law enforcement, increasingly make use of video from surveillance systems and camera phones owned by non-government entities.Making advanced and standardized motion imaging technology available to private and commercial users at cost-effective prices would benefit all parties. In particular, incorporating thermal infrared into commercial surveillance systems offers substantial benefits beyond night vision capability. Face rendering is a process to facilitate exploitation of thermal infrared surveillance imagery from the general area of a crime scene, to assist investigations with and without cooperating eyewitnesses. Face rendering automatically generates greyscale representations similar to police artist sketches for faces in surveillance imagery collected from proximate locations and times to a crime under investigation. Near-realtime generation of face renderings can provide law enforcement with an investigation tool to assess witness memory and credibility, and integrate reports from multiple eyewitnesses, Renderings can be quickly disseminated through social media to warn of a person who may pose an immediate threat, and to solicit the public's help in identifying possible suspects and witnesses. Renderings are pose-standardized so as to not divulge the presence and location of eyewitnesses and surveillance cameras. Incorporation of thermal infrared imaging into commercial surveillance systems will significantly improve system performance, and reduce manual review times, at an incremental cost that will continue to decrease. Benefits to criminal justice would include improved reliability of eyewitness testimony and improved accuracy of distinguishing among minority groups in eyewitness and surveillance identifications.

  14. Collaborative Graphic Rendering for Improving Visual Experience

    Science.gov (United States)

    Wu, Xiaoxin; Pei, Guodong

    Handheld devices such as UMPC, though convenient, bear weakness of size constraint for display. To mitigate such a problem and enhance user experience for owners of small devices, in this paper we design a collaborative rendering platform. When running game graphic applications at a handheld, the generated OpenGL graphic commands are intercepted and then delivered to a device with a larger display. The graphics are rendered and displayed at that device. The performance of the collaborative rendering platform is determined by graphic computing resources and network bandwidth. Analysis and simulation prove that other than providing a better display, the collaborative system can improve game experience also by increasing frame rates. In particular, at a low computing cost, a further collaboration between GPUs of collaborators can improve frame rate by eliminating the negative impact from network delay on applications that require GPU feedback.

  15. Adaptive Rendering Based on Visual Acuity Equations

    Institute of Scientific and Technical Information of China (English)

    2001-01-01

    A new method of adaptable rendering for interaction in Virtual Environment(VE) through different visual acuity equations is proposed. An acuity factor equation of luminance vision is first given. Secondly, five equations which calculate the visual acuity through visual acuity factors are presented, and adaptive rendering strategy based on different visual acuity equations is given. The VE system may select one of them on the basis of the host's load, hereby select LOD for each model which would be rendered. A coarser LOD is selected where the visual acuity is lower, and a better LOD is used where it is higher. This method is tested through experiments and the experimental results show that it is effective.

  16. Rendering Falling Leaves on Graphics Hardware

    Directory of Open Access Journals (Sweden)

    Marcos Balsa

    2008-04-01

    Full Text Available There is a growing interest in simulating natural phenomena in computer graphics applications. Animating natural scenes in real time is one of the most challenging problems due to the inherent complexity of their structure, formed by millions of geometric entities, and the interactions that happen within. An example of natural scenario that is needed for games or simulation programs are forests. Forests are difficult to render because the huge amount of geometric entities and the large amount of detail to be represented. Moreover, the interactions between the objects (grass, leaves and external forces such as wind are complex to model. In this paper we concentrate in the rendering of falling leaves at low cost. We present a technique that exploits graphics hardware in order to render thousands of leaves with different falling paths in real time and low memory requirements.

  17. Mobile Volume Rendering: Past, Present and Future.

    Science.gov (United States)

    Noguera, José M; Jiménez, J Roberto

    2016-02-01

    Volume rendering has been a relevant topic in scientific visualization for the last decades. However, the exploration of reasonably big volume datasets requires considerable computing power, which has limited this field to the desktop scenario. But the recent advances in mobile graphics hardware have motivated the research community to overcome these restrictions and to bring volume graphics to these ubiquitous handheld platforms. This survey presents the past and present work on mobile volume rendering, and is meant to serve as an overview and introduction to the field. It proposes a classification of the current efforts and covers aspects such as advantages and issues of the mobile platforms, rendering strategies, performance and user interfaces. The paper ends by highlighting promising research directions to motivate the development of new and interesting mobile volume solutions. PMID:26731459

  18. Blender cycles lighting and rendering cookbook

    CERN Document Server

    Iraci, Bernardo

    2013-01-01

    An in-depth guide full of step-by-step recipes to explore the concepts behind the usage of Cycles. Packed with illustrations, and lots of tips and tricks; the easy-to-understand nature of the book will help the reader understand even the most complex concepts with ease.If you are a digital artist who already knows your way around Blender, and you want to learn about the new Cycles' rendering engine, this is the book for you. Even experts will be able to pick up new tips and tricks to make the most of the rendering capabilities of Cycles.

  19. Haptic rendering for simulation of fine manipulation

    CERN Document Server

    Wang, Dangxiao; Zhang, Yuru

    2014-01-01

    This book introduces the latest progress in six degrees of freedom (6-DoF) haptic rendering with the focus on a new approach for simulating force/torque feedback in performing tasks that require dexterous manipulation skills. One of the major challenges in 6-DoF haptic rendering is to resolve the conflict between high speed and high fidelity requirements, especially in simulating a tool interacting with both rigid and deformable objects in a narrow space and with fine features. The book presents a configuration-based optimization approach to tackle this challenge. Addressing a key issue in man

  20. Valaisukartat reaaliaikaisessa renderöinnissä

    OpenAIRE

    Ylimäki, Juha

    2011-01-01

    Tässä toiminnallisessa opinnäytetyössä toteutettiin reaaliaikaisen ympäristön valaisu valaisukarttoja hyödyntäen. Tavoitteena oli tutkia, mitä kaikkea on otettava huomioon, kun renderöidään valaisukartoitus reaaliaikaiseen pelimoottoriin, joka tässä opinnäytetyössä on Unity. Ohjelmat, joita opinnäytetyössä käytettiin, olivat Autodesk 3ds Max mallintamiseen ja renderöintiin, Adobe Photoshop valaisukarttojen jälkikäsittelyyn ja Unity reaaliaikaisen sovelluksen toteuttamiseen. Opinnäytetyö...

  1. Use of GPU Functionality in Volume Rendering

    OpenAIRE

    Eide, Kristian Edvard Nigar

    2005-01-01

    Volume rendering describes the processes of creating a 2D projection of a 3D discretely sampled data set. This field has a number of applications, most notably within medical imaging, where the output of CT and MRI scanners is a volume data set, as well as geology where seismic surveys are visualized as an aid when searching for oil & gas. Rendering a volume is a computationally intensive task due to the large amount of data that needs to be processed, and it is only recently, with the a...

  2. Digital color acquisition, perception, coding and rendering

    CERN Document Server

    Fernandez-Maloigne, Christine; Macaire, Ludovic

    2013-01-01

    In this book the authors identify the basic concepts and recent advances in the acquisition, perception, coding and rendering of color. The fundamental aspects related to the science of colorimetry in relation to physiology (the human visual system) are addressed, as are constancy and color appearance. It also addresses the more technical aspects related to sensors and the color management screen. Particular attention is paid to the notion of color rendering in computer graphics. Beyond color, the authors also look at coding, compression, protection and quality of color images and videos.

  3. GPU Pro 5 advanced rendering techniques

    CERN Document Server

    Engel, Wolfgang

    2014-01-01

    In GPU Pro5: Advanced Rendering Techniques, section editors Wolfgang Engel, Christopher Oat, Carsten Dachsbacher, Michal Valient, Wessam Bahnassi, and Marius Bjorge have once again assembled a high-quality collection of cutting-edge techniques for advanced graphics processing unit (GPU) programming. Divided into six sections, the book covers rendering, lighting, effects in image space, mobile devices, 3D engine design, and compute. It explores rasterization of liquids, ray tracing of art assets that would otherwise be used in a rasterized engine, physically based area lights, volumetric light

  4. Gene silencing and homology-dependent gene silencing in Arabidopsis: genetic modifiers and DNA methylation.

    OpenAIRE

    Furner, I J; Sheikh, M. A.; Collett, C E

    1998-01-01

    Transgenes inserted into the plant genome can become inactive (gene silencing) or result in silencing of homologous cellular genes [homology-dependent gene silencing (HDG silencing)]. In an earlier study we reported HDG silencing of chalcone synthase (CHS) in Arabidopsis. This study concerns genetic revertants of one of the CHS HDG-silencing transgenic homozygotes. Two monogenic recessive trans-acting mutations (hog1 and ddm1) that impair gene silencing and HDG silencing were identified. Thes...

  5. The draft genome of the transgenic tropical fruit tree papaya (Carica papaya Linnaeus).

    Science.gov (United States)

    We report a draft genome sequence of ‘SunUp’ papaya, the first commercial virus-resistant transgenic fruit tree crop. The papaya genome has more than two times the DNA but about 28% fewer genes than the genome of the related botanical model Arabidopsis. A lack of genome duplication, atypical of angi...

  6. Generation of Transgenic Mice

    OpenAIRE

    Cho, Andrew; Haruyama, Naoto; Kulkarni, Ashok B.

    2009-01-01

    This unit describes detailed step-by-step protocols, reagents, and equipment required for successful generation of transgenic mice using pronuclear injection. The experimental methods and practical tips given here will help guide beginners in understanding what is required and what to avoid in these standard protocols for efficiently generating transgenic mice.

  7. Durability of renderings of historical buildings

    OpenAIRE

    Gomdenn, Prayash

    2016-01-01

    Historical, cultural and architectural values of historical buildings and structures signify the importance of their conservation. Several deterioration mechanisms associated with different environmental or weather conditions are responsible for damaging rendering mortars of historical buildings. These deterioration mechanisms may act individually or jointly, making it important to understand each deterioration mechanism and their coupled effects. This research investigated the deteriorati...

  8. Rendering Visible: Painting and Sexuate Subjectivity

    Science.gov (United States)

    Daley, Linda

    2015-01-01

    In this essay, I examine Luce Irigaray's aesthetic of sexual difference, which she develops by extrapolating from Paul Klee's idea that the role of painting is to render the non-visible rather than represent the visible. This idea is the premise of her analyses of phenomenology and psychoanalysis and their respective contributions to understanding…

  9. Haptic rendering for dental training system

    Institute of Scientific and Technical Information of China (English)

    WANG DangXiao; ZHANG YuRu; WANG Yong; L(U) PeiJun; ZHOU RenGe; ZHOU WanLin

    2009-01-01

    Immersion and Interaction are two key features of virtual reality systems,which are especially important for medical applications.Based on the requirement of motor skill training in dental surgery,haptic rendering method based on triangle model is investigated in this paper.Multi-rate haptic rendering architecture is proposed to solve the contradiction between fidelity and efficiency requirements.Realtime collision detection algorithm based on spatial partition and time coherence is utilized to enable fast contact determination.Proxy-based collision response algorithm is proposed to compute surface contact point.Cutting force model based on piecewise contact transition model is proposed for dental drilling simulation during tooth preparation.Velocity-driven levels of detail hapUc rendering algorithm is proposed to maintain high update rate for complex scenes with a large number of triangles.Hapticvisual collocated dental training prototype is established using half-mirror solution.Typical dental operations have been realized Including dental caries exploration,detection of boundary within dental crose-section plane,and dental drilling during tooth preparation.The haptic rendering method is a fundamental technology to improve Immersion and interaction of virtual reality training systems,which is useful not only in dental training,but also in other surgical training systems.

  10. Rendering Caustics on Non-Lambertian Surfaces

    DEFF Research Database (Denmark)

    Jensen, Henrik Wann

    1997-01-01

    This paper presents a new technique for rendering caustics on non-Lambertian surfaces. The method is based on an extension of the photon map which removes previous restrictions limiting the usage to Lambertian surfaces. We add information about the incoming direction to the photons and this allow...

  11. Color rendering indices in global illumination methods

    Science.gov (United States)

    Geisler-Moroder, David; Dür, Arne

    2009-02-01

    Human perception of material colors depends heavily on the nature of the light sources used for illumination. One and the same object can cause highly different color impressions when lit by a vapor lamp or by daylight, respectively. Based on state-of-the-art colorimetric methods we present a modern approach for calculating color rendering indices (CRI), which were defined by the International Commission on Illumination (CIE) to characterize color reproduction properties of illuminants. We update the standard CIE method in three main points: firstly, we use the CIELAB color space, secondly, we apply a Bradford transformation for chromatic adaptation, and finally, we evaluate color differences using the CIEDE2000 total color difference formula. Moreover, within a real-world scene, light incident on a measurement surface is composed of a direct and an indirect part. Neumann and Schanda1 have shown for the cube model that interreflections can influence the CRI of an illuminant. We analyze how color rendering indices vary in a real-world scene with mixed direct and indirect illumination and recommend the usage of a spectral rendering engine instead of an RGB based renderer for reasons of accuracy of CRI calculations.

  12. Rapid Decimation for Direct Volume Rendering

    Science.gov (United States)

    Gibbs, Jonathan; VanGelder, Allen; Verma, Vivek; Wilhelms, Jane

    1997-01-01

    An approach for eliminating unnecessary portions of a volume when producing a direct volume rendering is described. This reduction in volume size sacrifices some image quality in the interest of rendering speed. Since volume visualization is often used as an exploratory visualization technique, it is important to reduce rendering times, so the user can effectively explore the volume. The methods presented can speed up rendering by factors of 2 to 3 with minor image degradation. A family of decimation algorithms to reduce the number of primitives in the volume without altering the volume's grid in any way is introduced. This allows the decimation to be computed rapidly, making it easier to change decimation levels on the fly. Further, because very little extra space is required, this method is suitable for the very large volumes that are becoming common. The method is also grid-independent, so it is suitable for multiple overlapping curvilinear and unstructured, as well as regular, grids. The decimation process can proceed automatically, or can be guided by the user so that important regions of the volume are decimated less than unimportant regions. A formal error measure is described based on a three-dimensional analog of the Radon transform. Decimation methods are evaluated based on this metric and on direct comparison with reference images.

  13. 3-D Volume Rendering of Sand Specimen

    Science.gov (United States)

    2004-01-01

    Computed tomography (CT) images of resin-impregnated Mechanics of Granular Materials (MGM) specimens are assembled to provide 3-D volume renderings of density patterns formed by dislocation under the external loading stress profile applied during the experiments. Experiments flown on STS-79 and STS-89. Principal Investigator: Dr. Stein Sture

  14. Occlusion Culling and Hardware Accelerated Volume Rendering

    OpenAIRE

    Meissner, Michael

    2000-01-01

    Within this dissertation, a set of algorithmic optimizations are developed, enabling significant performance improvements due to a much better utilization of the available bandwidth. Additionally, new architectural concepts circumventing the bottle-necks of currently available general purpose graphics hardware are presented. In the field of polygon rendering, a unique mechanism for hardware supported occlusion queries to cull geometry prior to geometry transformation --- sav...

  15. ProteinShader: illustrative rendering of macromolecules

    Directory of Open Access Journals (Sweden)

    Weber Joseph R

    2009-03-01

    Full Text Available Abstract Background Cartoon-style illustrative renderings of proteins can help clarify structural features that are obscured by space filling or balls and sticks style models, and recent advances in programmable graphics cards offer many new opportunities for improving illustrative renderings. Results The ProteinShader program, a new tool for macromolecular visualization, uses information from Protein Data Bank files to produce illustrative renderings of proteins that approximate what an artist might create by hand using pen and ink. A combination of Hermite and spherical linear interpolation is used to draw smooth, gradually rotating three-dimensional tubes and ribbons with a repeating pattern of texture coordinates, which allows the application of texture mapping, real-time halftoning, and smooth edge lines. This free platform-independent open-source program is written primarily in Java, but also makes extensive use of the OpenGL Shading Language to modify the graphics pipeline. Conclusion By programming to the graphics processor unit, ProteinShader is able to produce high quality images and illustrative rendering effects in real-time. The main feature that distinguishes ProteinShader from other free molecular visualization tools is its use of texture mapping techniques that allow two-dimensional images to be mapped onto the curved three-dimensional surfaces of ribbons and tubes with minimum distortion of the images.

  16. Shapes and textures for rendering coral

    Energy Technology Data Exchange (ETDEWEB)

    Max, N.L. (Lawrence Livermore National Lab., CA (USA)); Wyvill, G. (Otago Univ., Dunedin (New Zealand))

    1990-10-18

    A growth algorithm has been developed to build coral shapes out of a tree of spheres. A volume density defined by the spheres is contoured to give a soft object.'' The resulting contour surfaces are rendered by ray tracing, using a generalized volume texture to produce shading and bump mapped'' normal perturbations. 16 refs., 8 figs.

  17. Glutathione Dynamics in Arabidopsis Seed Development and Germination

    OpenAIRE

    Sumugat, Mae Rose S.

    2004-01-01

    Seed desiccation and germination have great potential for oxidative stress. Glutathione, one of the most abundant antioxidants in plant cells, is a crucial to the plant's defense mechanisms. To better understand glutathione's responses during these two stages, we examined its dynamics in wildtype Arabidopsis seeds and in a transgenic line containing an antisense glutathione reductase2 (anGR2) cDNA insert. Seeds from the two genotypes were compared morphologically. Glutathione levels in maturi...

  18. Multidimensional fluorescence microscopy of multiple organelles in Arabidopsis seedlings

    Directory of Open Access Journals (Sweden)

    Morales Andrea

    2008-05-01

    Full Text Available Abstract Background The isolation of green fluorescent protein (GFP and the development of spectral variants over the past decade have begun to reveal the dynamic nature of protein trafficking and organelle motility. In planta analyses of this dynamic process have typically been limited to only two organelles or proteins at a time in only a few cell types. Results We generated a transgenic Arabidopsis plant that contains four spectrally different fluorescent proteins. Nuclei, plastids, mitochondria and plasma membranes were genetically tagged with cyan, red, yellow and green fluorescent proteins, respectively. In addition, methods to track nuclei, mitochondria and chloroplasts and quantify the interaction between these organelles at a submicron resolution were developed. These analyzes revealed that N-ethylmaleimide disrupts nuclear-mitochondrial but not nuclear-plastids interactions in root epidermal cells of live Arabidopsis seedlings. Conclusion We developed a tool and associated methods for analyzing the complex dynamic of organelle-organelle interactions in real time in planta. Homozygous transgenic Arabidopsis (Kaleidocell is available through Arabidopsis Biological Resource Center.

  19. Can transgenic rice cause ecological risks through transgene escape?

    Institute of Scientific and Technical Information of China (English)

    2003-01-01

    Alien transgene escape from genetically engineered rice to non-transgenic varieties or close wild relatives (including weedy rice) may lead to unpredictable ecological risks. However, for transgene escape to occur three conditions need to be met: (i) spatially, transgenic rice and its non-transgenic counterparts or wild relatives should have sympatric distributions; (ii) temporally, the flowering time of transgenic rice and the non-transgenic varieties or wild relatives should overlap; and (iii) biologically, transgenic rice and its wild relative species should have such a sufficiently close relationship that their interspecific hybrids can have normal generative reproduction. This paper presents research data on the geographic distribution, flowering habits, interspecific hybridization, and gene flow of cultivated rice (Oryza sativa) and its closely related wild relatives containing the AA genome. The objective is to estimate the possibility of transgene escape to non-transgenic rice varieties and wild relatives of rice, which may result in unpredictable ecological risks.

  20. Remote interactive direct volume rendering of AMR data

    Energy Technology Data Exchange (ETDEWEB)

    Kreylos, Oliver; Weber, Gunther H.; Bethel, E. Wes; Shalf, John M.; Hamann, Bernd; Joy, Kenneth I.

    2002-03-28

    We describe a framework for direct volume rendering of adaptive mesh refinement (AMR) data that operates directly on the hierarchical grid structure, without the need to resample data onto a single, uniform rectilinear grid. The framework can be used for a range of renderers optimized for particular hardware architectures: a hardware-assisted renderer for single-processor graphics workstations, and a massively parallel software-only renderer for supercomputers. It is also possible to use the framework for distributed rendering servers. By exploiting the multiresolution structure of AMR data, the hardware-assisted renderers can render large AMR data sets at interactive rates, even if the data is stored remotely.

  1. Remote interactive direct volume rendering of AMR data

    International Nuclear Information System (INIS)

    We describe a framework for direct volume rendering of adaptive mesh refinement (AMR) data that operates directly on the hierarchical grid structure, without the need to resample data onto a single, uniform rectilinear grid. The framework can be used for a range of renderers optimized for particular hardware architectures: a hardware-assisted renderer for single-processor graphics workstations, and a massively parallel software-only renderer for supercomputers. It is also possible to use the framework for distributed rendering servers. By exploiting the multiresolution structure of AMR data, the hardware-assisted renderers can render large AMR data sets at interactive rates, even if the data is stored remotely

  2. Pipelined Sort-last Rendering: Scalability, Performance and Beyond

    OpenAIRE

    Cavin, Xavier; Mion, Christophe

    2006-01-01

    We present in this paper a theoretical and practical performance analysis of pipelined sort-last rendering for both polygonal and volume rendering. Theoretical peak performance and scalability are studied, exhibiting maximum attainable framerates of 19 fps (volume rendering with back-to-front alpha blending) and 11 fps (polygonal rendering with Z-buffer compositing) for a 1280×1024 display on a Gigabit Ethernet cluster. We show that our implementation of pipelined sort-last rendering on a 17-...

  3. Accelerated Volume Rendering Using Level-Of-Detail Technology

    OpenAIRE

    Xu, Qian

    2009-01-01

    Nowadays, more and more virtual manufacturing simulations use volume rendering technology to enhance the display results and effects. When using large volume data sets, normal rendering algorithms trade off image quality against rendering speed. However, it is often not necessary to render the whole data set at some particular observation angles. If the unnecessary data ( during a special defined condition) can be edited, the rendering time can be saved and the frame rate can be rais...

  4. Anti-Aliased Rendering of Water Surface

    Institute of Scientific and Technical Information of China (English)

    Xue-Ying Qin; Eihachiro Nakamae; Wei Hua; Yasuo Nagai; Qun-Sheng Peng

    2004-01-01

    Water surface is one of the most important components of landscape scenes. When rendering spacious far from the viewpoint. This is because water surface consists of stochastic water waves which are usually modeled by periodic bump mapping. The incident rays on the water surface are actually scattered by the bumped waves,pattern, we estimate this solid angle of reflected rays and trace these rays. An image-based accelerating method is adopted so that the contribution of each reflected ray can be quickly obtained without elaborate intersection calculation. We also demonstrate anti-aliased shadows of sunlight and skylight on the water surface. Both the rendered images and animations show excellent effects on the water surface of a reservoir.

  5. Defects of organization in rendering medical aid

    OpenAIRE

    Shavkat Islamov

    2010-01-01

    The defects of organization at the medical institution mean disturbance of rules, norms and order of rendering of medical aid. The number of organization defects in Uzbekistan increased from 20.42%, in 1999 to 25.46% in 2001 with gradual decrease to 19.9% in 2003 and 16.66%, in 2006 and gradual increase to 21.95% and 28.28% (P

  6. Rendering mortars with incorporation of ceramic aggregates

    OpenAIRE

    Mª Rosário Veiga; João Silva; Jorge Brito

    2008-01-01

    In this paper the experimental evaluation of the water-related performance of rendering mortars with incorporation of recycled products is presented, based on three different research vectors: addition of fine recycled aggregates; reduction of the cement content (with simultaneous addition of fines); and replacement of sand with recycled material, with the same overall grading curve. The material presented here as recyclable is brick waste from the ceramics and construction industries.

  7. Progressive Perceptual Audio Rendering of Complex Scenes

    OpenAIRE

    Moeck, Thomas; Bonneel, Nicolas; Tsingos, Nicolas; Drettakis, George; Viaud-Delmon, Isabelle; Aloza, David

    2007-01-01

    Despite recent advances, including sound source clustering and perceptual auditory masking, high quality rendering of complex virtual scenes with thousands of sound sources remains a challenge. Two major bottlenecks appear as the scene complexity increases: the cost of clustering itself, and the cost of pre-mixing source signals within each cluster. In this paper, we first propose an improved hierarchical clustering algorithm that remains efficient for large numbers of sources and clusters wh...

  8. 3D Rendering - Techniques and Challenges

    OpenAIRE

    Ekta Walia; Vishal Verma

    2010-01-01

    Computer generated images and animations are getting more and more common. They are used in many different contexts such as movies,mobiles, medical visualization, architectural visualization and CAD. Advanced ways of describing surface and light source properties are important to ensure that artists are able to create realistic and stylish looking images. Even when using advanced rendering algorithms such as ray tracing, time required for shading may contribute towards a large part of the ima...

  9. Obscurance-based Volume Rendering Framework

    OpenAIRE

    Ruiz, Marc; Boada, Imma; Viola, Ivan; Bruckner, Stefan; Feixas, Miquel; Sbert, Mateu

    2008-01-01

    lighting effects in a faster way than global illumination. Its application in volume visualization is of special interest since it permits us to generate a high quality rendering at a low cost. In this paper, we propose an obscurancebased framework that allows us to obtain realistic and illustrative volume visualizations in an interactive manner. Obscurances can include color bleeding effects without additional cost. Moreover, we obtain a saliency map from the gradient of obscuran...

  10. A Perceptive Evaluation of Volume Rendering Techniques

    OpenAIRE

    Boucheny, Christian; Bonneau, Georges-Pierre; Droulez, Jacques; Thibault, Guillaume; Ploix, Stéphane

    2007-01-01

    The display of space filling data is still a challenge for the community of visualization. Direct Volume Rendering (DVR) is one of the most important techniques developed to achieve direct perception of such volumetric data. It is based on semi-transparent representations, where the data are accumulated in a depth-dependent order. However, it produces images that may be difficult to understand, and thus several techniques have been proposed so as to improve its effectiveness, using for instan...

  11. Fast projective volume rendering: approximating the rendering process or simplifying the data ?

    OpenAIRE

    Cignoni, Paolo; Montani, Claudio; Sarti, D.; Scopigno, Roberto

    1995-01-01

    How to render very complex datasets, and yet maintain interactive response times, is a hot topic in volume rendering. In this paper we focus on projective visualization of datasets represented via tetrahedral tessellations. Direct projective visualization is performed by sorting tetrahedra with respect to view direction and then by projecting them onto the screen. Different sorting algorythms and "per tetrahedra" projection techniques are reviewed and evaluated. anew method fot tetrahedra pro...

  12. Transgenic Animal Mutation Assays

    Institute of Scientific and Technical Information of China (English)

    Tao Chen; Ph.D.D.A.B.T.

    2005-01-01

    @@ The novel transgenic mouse and rat mutation assays have provided a tool for analyzing in vivo mutation in any tissue, thus permitting the direct comparison of cancer incidence with mutant frequency.

  13. Transgenic mice: beyond the knockout

    OpenAIRE

    Miller, R. Lance

    2010-01-01

    Transgenic mice have had a tremendous impact on biomedical research. Most researchers are familiar with transgenic mice that carry Cre recombinase (Cre) and how they are used to create conditional knockouts. However, some researchers are less familiar with many of the other types of transgenic mice and their applications. For example, transgenic mice can be used to study biochemical and molecular pathways in primary cultures and cell suspensions derived from transgenic mice, cell-cell interac...

  14. DEPENDENCE OF STEM CELL FATE IN ARABIDOPSIS ON A FEEDBACK LOOP REGULATED BY CLV3 ACTIVITY

    Science.gov (United States)

    The fate of stem cells in plant meristems is governed by directional signalling systems that are regulated by negative feedback. In Arabidopsis, the CLAVATA (CLV) genes encode the essential components of a negative, stem cell restricting pathway. We have used transgenic plants over-expressing CLV3 t...

  15. Heterologous expression of the Arabidopsis etr1-1 allele inhibits the senescence of carnation flowers

    NARCIS (Netherlands)

    Bovy, A.G.; Angenent, G.C.; Dons, H.J.M.; Altvorst, van A.

    1999-01-01

    The Arabidopsis thaliana etr1-1 allele, capable of conferring ethylene insensitivity in a heterologous host, was introduced into transgenic carnation plants. This gene was expressed under control of either its own promoter, the constitutive CaMV 35S promoter or the flower-specific petunia FBP1 promo

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

    Directory of Open Access Journals (Sweden)

    Xue-Rong eZhou

    2014-09-01

    Full Text Available Metabolic engineering of omega-3 long-chain (≥C20 polyunsaturated fatty acids (ω3 LC-PUFA in oilseeds has been one of the key metabolic engineering targets in recent years. By expressing a transgenic pathway for enhancing the synthesis of the ω3 LC-PUFA docosahexaenoic acid (DHA from endogenous -linolenic acid (ALA, we obtained the production of fish oil-like proportions of DHA in Arabidopsis seed oil. Liquid chromatography-mass spectrometry (LC-MS was used to characterize the triacylglycerol (TAG, diacylglycerol (DAG and phospholipid (PL lipid classes in the transgenic and wild type Arabidopsis seeds at both developing and mature stages. The analysis identified the appearance of several abundant DHA-containing phosphatidylcholine (PC, DAG and TAG molecular species in mature seeds. The relative abundances of PL, DAG and TAG species showed a preferred combination of LC-PUFA with ALA in the transgenic seeds, where LC-PUFA were esterified in positions usually occupied by 20:1ω9. Trace amounts of di-DHA PC and tri-DHA TAG were identified, and confirmed by high resolution MS/MS. Studying the lipidome in transgenic seeds provides insights into where DHA accumulated and composed with other fatty acids of neutral and phospholipids from the developing and mature seeds.

  17. Transgene mus som sygdomsmodeller

    DEFF Research Database (Denmark)

    Schuster, Mikkel Bruhn; Porse, Bo Torben

    2003-01-01

    Transgenic animal models have proven to be useful tools in understanding both basic biology and the events associated with disease. Recent technical advances in the area of genomic manipulation in combination with the availability of the human and murine genomic sequences now allow the precise...... tailoring of the mouse genome. In this review we describe a few systems in which transgenic animal models have been employed for the purpose of studying the etiology of human diseases. Udgivelsesdato: 2003-Feb-17...

  18. Profilin Plays a Role in Cell Elongation, Cell Shape Maintenance, and Flowering in Arabidopsis

    DEFF Research Database (Denmark)

    Ramachandran, S.; Christensen, Hans Erik Mølager; Ishimaru, Y.;

    2000-01-01

    Profilin (PFN) is an ubiquitous, low-M-r, actin-binding protein involved in the organization of the cytoskeleton of eukaryotes including higher plants. PFNs are encoded by a multigene family in Arabidopsis. We have analyzed in vivo functions of Arabidopsis PFN by generating transgenic plants...... carrying a 35S-PFN-1 or 35S-antisense PFN-1 transgene. Etiolated seedlings underexpressing PFN (PFN-U) displayed an overall dwarf phenotype with short hypocotyls whose lengths were 20% to 25% that of wild type (WT) at low temperatures. Light-grown PFN-U plants were smaller in stature and flowered early...... expressed in the vascular bundles of cotyledons and leaves. Our results show that Arabidopsis PFNs play a role in cell elongation, cell shape maintenance, polarized growth of root hair, and unexpectedly, in determination of flowering time....

  19. Structure-function relationships during transgenic telomerase expression in Arabidopsis

    Czech Academy of Sciences Publication Activity Database

    Zachová, D.; Fojtová, Miloslava; Dvořáčková, Martina; Mozgová, I.; Lermontova, I.; Peška, Vratislav; Schubert, I.; Fajkus, Jiří; Sýkorová, Eva

    2013-01-01

    Roč. 149, č. 1 (2013), s. 114-126. ISSN 0031-9317 R&D Projects: GA AV ČR(CZ) IAA500040801; GA ČR(CZ) ED1.1.00/02.0068 Institutional research plan: CEZ:AV0Z50040702 Institutional support: RVO:68081707 Keywords : RNA-BINDING DOMAIN * REVERSE-TRANSCRIPTASE * NUCLEOLAR LOCALIZATION Subject RIV: BO - Biophysics Impact factor: 3.262, year: 2013

  20. Functional analysis of the Hikeshi-like protein and its interaction with HSP70 in Arabidopsis

    Energy Technology Data Exchange (ETDEWEB)

    Koizumi, Shinya; Ohama, Naohiko; Mizoi, Junya [Laboratory of Plant Molecular Physiology, Graduate School of Agricultural and Life Sciences, The University of Tokyo, 1-1-1 Yayoi, Bunkyo-ku, Tokyo 113-8657 (Japan); Shinozaki, Kazuo [RIKEN Plant Science Center, 1-7-22 Suehiro-cho, Tsurumi, Yokohama, Kanagawa 230-0045 (Japan); Yamaguchi-Shinozaki, Kazuko, E-mail: akys@mail.ecc.u-tokyo.ac.jp [Laboratory of Plant Molecular Physiology, Graduate School of Agricultural and Life Sciences, The University of Tokyo, 1-1-1 Yayoi, Bunkyo-ku, Tokyo 113-8657 (Japan)

    2014-07-18

    Highlights: • HKL, a Hikeshi homologous gene is identified in Arabidopsis. • HKL interacts with two HSP70 isoforms and regulates the subcellular localization of HSC70-1. • The two HSP70 translocate into nucleus in response to heat stress. • Overexpression of HKL confers thermotolerance in transgenic plants. - Abstract: Heat shock proteins (HSPs) refold damaged proteins and are an essential component of the heat shock response. Previously, the 70 kDa heat shock protein (HSP70) has been reported to translocate into the nucleus in a heat-dependent manner in many organisms. In humans, the heat-induced translocation of HSP70 requires the nuclear carrier protein Hikeshi. In the Arabidopsis genome, only one gene encodes a protein with high homology to Hikeshi, and we named this homolog Hikeshi-like (HKL) protein. In this study, we show that two Arabidopsis HSP70 isoforms accumulate in the nucleus in response to heat shock and that HKL interacts with these HSP70s. Our histochemical analysis revealed that HKL is predominantly expressed in meristematic tissues, suggesting the potential importance of HKL during cell division in Arabidopsis. In addition, we show that HKL regulates HSP70 localization, and HKL overexpression conferred thermotolerance to transgenic Arabidopsis plants. Our results suggest that HKL plays a positive role in the thermotolerance of Arabidopsis plants and cooperatively interacts with HSP70.

  1. GPU Pro 4 advanced rendering techniques

    CERN Document Server

    Engel, Wolfgang

    2013-01-01

    GPU Pro4: Advanced Rendering Techniques presents ready-to-use ideas and procedures that can help solve many of your day-to-day graphics programming challenges. Focusing on interactive media and games, the book covers up-to-date methods producing real-time graphics. Section editors Wolfgang Engel, Christopher Oat, Carsten Dachsbacher, Michal Valient, Wessam Bahnassi, and Sebastien St-Laurent have once again assembled a high-quality collection of cutting-edge techniques for advanced graphics processing unit (GPU) programming. Divided into six sections, the book begins with discussions on the abi

  2. Defects of organization in rendering medical aid

    Directory of Open Access Journals (Sweden)

    Shavkat Islamov

    2010-09-01

    Full Text Available The defects of organization at the medical institution mean disturbance of rules, norms and order of rendering of medical aid. The number of organization defects in Uzbekistan increased from 20.42%, in 1999 to 25.46% in 2001 with gradual decrease to 19.9% in 2003 and 16.66%, in 2006 and gradual increase to 21.95% and 28.28% (P<0.05 in 2005 and 2008. Among the groups of essential defects of organization there were following: disturbance of transportation rules, lack of dispensary care, shortcomings in keeping medical documentation.

  3. GPU PRO 3 Advanced rendering techniques

    CERN Document Server

    Engel, Wolfgang

    2012-01-01

    GPU Pro3, the third volume in the GPU Pro book series, offers practical tips and techniques for creating real-time graphics that are useful to beginners and seasoned game and graphics programmers alike. Section editors Wolfgang Engel, Christopher Oat, Carsten Dachsbacher, Wessam Bahnassi, and Sebastien St-Laurent have once again brought together a high-quality collection of cutting-edge techniques for advanced GPU programming. With contributions by more than 50 experts, GPU Pro3: Advanced Rendering Techniques covers battle-tested tips and tricks for creating interesting geometry, realistic sha

  4. Haptic rendering foundations, algorithms, and applications

    CERN Document Server

    Lin, Ming C

    2008-01-01

    For a long time, human beings have dreamed of a virtual world where it is possible to interact with synthetic entities as if they were real. It has been shown that the ability to touch virtual objects increases the sense of presence in virtual environments. This book provides an authoritative overview of state-of-theart haptic rendering algorithms and their applications. The authors examine various approaches and techniques for designing touch-enabled interfaces for a number of applications, including medical training, model design, and maintainability analysis for virtual prototyping, scienti

  5. Rendering of 3D Dynamic Virtual Environments

    CERN Document Server

    Catanese, Salvatore; Fiumara, Giacomo; Pagano, Francesco

    2011-01-01

    In this paper we present a framework for the rendering of dynamic 3D virtual environments which can be integrated in the development of videogames. It includes methods to manage sounds and particle effects, paged static geometries, the support of a physics engine and various input systems. It has been designed with a modular structure to allow future expansions. We exploited some open-source state-of-the-art components such as OGRE, PhysX, ParticleUniverse, etc.; all of them have been properly integrated to obtain peculiar physical and environmental effects. The stand-alone version of the application is fully compatible with Direct3D and OpenGL APIs and adopts OpenAL APIs to manage audio cards. Concluding, we devised a showcase demo which reproduces a dynamic 3D environment, including some particular effects: the alternation of day and night infuencing the lighting of the scene, the rendering of terrain, water and vegetation, the reproduction of sounds and atmospheric agents.

  6. A Multiresolution Image Cache for Volume Rendering

    Energy Technology Data Exchange (ETDEWEB)

    LaMar, E; Pascucci, V

    2003-02-27

    The authors discuss the techniques and implementation details of the shared-memory image caching system for volume visualization and iso-surface rendering. One of the goals of the system is to decouple image generation from image display. This is done by maintaining a set of impostors for interactive display while the production of the impostor imagery is performed by a set of parallel, background processes. The system introduces a caching basis that is free of the gap/overlap artifacts of earlier caching techniques. instead of placing impostors at fixed, pre-defined positions in world space, the technique is to adaptively place impostors relative to the camera viewpoint. The positions translate with the camera but stay aligned to the data; i.e., the positions translate, but do not rotate, with the camera. The viewing transformation is factored into a translation transformation and a rotation transformation. The impostor imagery is generated using just the translation transformation and visible impostors are displayed using just the rotation transformation. Displayed image quality is improved by increasing the number of impostors and the frequency that impostors are re-rendering is improved by decreasing the number of impostors.

  7. An auxin responsive CLE gene regulates shoot apical meristem development in Arabidopsis

    Directory of Open Access Journals (Sweden)

    Hongyan eGuo

    2015-05-01

    Full Text Available Plant hormone auxin regulates most, if not all aspects of plant growth and development, including lateral root formation, organ pattering, apical dominance and tropisms. Peptide hormones are peptides with hormone activities. Some of the functions of peptide hormones in regulating plant growth and development are similar to that of auxin, however, the relationship between auxin and peptide hormones remains largely unknown. Here we report the identification of OsCLE48, a rice (Oryza sativa CLE (CLAVATA3/ENDOSPERM SURROUNDING REGION gene, as an auxin response gene, and the functional characterization of OsCLE48 in Arabidopsis and rice. OsCLE48 encodes a CLE peptide hormone that is similar to Arabidopsis CLEs. RT-PCR analysis showed that OsCLE48 was induced by exogenously application of IAA (indole-3-acetic acid, a naturally occurred auxin. Expression of integrated OsCLE48p:GUS reporter gene in transgenic Arabidopsis plants was also induced by exogenously IAA treatment. These results indicate that OsCLE48 is an auxin responsive gene. Histochemical staining showed that GUS activity was detected in all the tissue and organs of the OsCLE48p:GUS transgenic Arabidopsis plants. Expression of OsCLE48 under the control of the 35S promoter in Arabidopsis inhibited shoot apical meristem development. Expression of OsCLE48 under the control of the CLV3 native regulatory elements almost completely complemented clv3-2 mutant phenotypes, suggesting that OsCLE48 is functionally similar to CLV3. On the other hand, expression of OsCLE48 under the control of the 35S promoter in Arabidopsis has little, if any effects on root apical meristem development, and transgenic rice plants overexpressing OsCLE48 are morphologically indistinguishable from wild type plants, suggesting that the functions of some CLE peptides may not be fully conserved in Arabidopsis and rice.

  8. Efficiently rendering large volume data using texture mapping hardware

    OpenAIRE

    Tong, X; Tang, Z.; Tsang, WW; Wang, WP

    1999-01-01

    Volume rendering with texture mapping hardware is a fast volume rendering method available on high-end workstations. However, limited texture memory often prevents the method from being used to render large volume data efficiently. In this paper, we propose a new approach to fast rendering of large volume data with texture mapping hardware. Based on a new volume-loading pipeline, the volume data is preprocessed in such a way that only the volume data that contains object voxels are loaded int...

  9. Single-pass multi-view volume rendering

    OpenAIRE

    Hübner, T; Pajarola, R.

    2007-01-01

    In this paper, we introduce a new direct volume rendering (DVR) algorithm for multi-view auto-stereoscopic displays. Common multi-view methods perform multi-pass rendering (one pass for each view) and subsequent image compositing and masking for generating multiple views. The rendering time increases therefore linearly with the number of views, but sufficient frame-rates are achieved by sub-resolution rendering, at the expense of degraded image quality. To overcome these disadvantages for DVR...

  10. Validation of a colour rendering index based on memory colours

    OpenAIRE

    Smet, Kevin; Jost-Boissard, Sophie; Ryckaert, Wouter; Deconinck, Geert; Hanselaer, Peter

    2010-01-01

    In this paper the performance of a colour rendering index based on memory colours is investigated in comparison with the current CIE Colour Rendering Index, the NIST Colour Quality Scale and visual appreciation results obtained at CNRS at Lyon University for a set of 3000K and 4000K LED light sources. The Pearson and Spearman correlation coefficients between each colour rendering metric and the two sets of visual results were calculated. It was found that the memory colour based colour render...

  11. Thermodynamic and structural properties of tuber starches from transgenic potato plants grown in vitro and in vivo

    NARCIS (Netherlands)

    Wasserman, L.A.; Sergeev, A.I.; Vasil'Ev, V.G.; Plashchina, I.G.; Aksenova, N.P.; Konstantinova, T.N.; Golyanovskaya, S.A.; Sergeeva, Lidia; Romanov, G.A.

    2015-01-01

    Potato plants harboring Phytochrome B (PHYB) gene from Arabidopsis thaliana or rol genes from Agrobacterium rhizogenes were used to study the effect of transgene expression on structure and properties of starch in tubers. Thermodynamic characteristics of starch (melting temperature, enthalpy of m

  12. X-Ray Volume Rendering through Two-Stage Splatting

    OpenAIRE

    Westenberg, Michel A.; Roerdink, Jos B. T. M.

    2000-01-01

    We consider the splatting method for X-ray rendering of volume data sets, and introduce two-stage splatting. This variant improves rendering speed by separating the splatting process in two stages: coefficient accumulation and convolution. We incorporate this variant into wavelet splatting, and obtain speedups in rendering time up to a factor of three for Haar and B-spline wavelets.

  13. Transgenic mosquitoes and the fight against malaria: managing technology push in a turbulent GMO world

    NARCIS (Netherlands)

    Knols, B.G.J.; Bossin, H.C.; Mukabana, W.R.; Robinson, A.S.

    2007-01-01

    Genetic modification (GM) of mosquitoes (which renders them genetically modified organisms, GMOs) offers opportunities for controlling malaria. Transgenic strains of mosquitoes have been developed and evaluation of these to 1) replace or suppress wild vector populations and 2) reduce transmission an

  14. Transgenic mice susceptible to poliovirus.

    OpenAIRE

    S. Koike; Taya, C; Kurata, T; Abe, S.; Ise, I; Yonekawa, H; Nomoto, A

    1991-01-01

    Poliovirus-sensitive transgenic mice were produced by introducing the human gene encoding cellular receptors for poliovirus into the mouse genome. Expression of the receptor mRNAs in tissues of the transgenic mice was analyzed by using RNA blot hybridization and the polymerase chain reaction. The human gene is expressed in many tissues of the transgenic mice just as in tissues of humans. The transgenic mice are susceptible to all three poliovirus serotypes, and the mice inoculated with poliov...

  15. Photon Differential Splatting for Rendering Caustics

    DEFF Research Database (Denmark)

    Frisvad, Jeppe Revall; Schjøth, Lars; Erleben, Kenny;

    2014-01-01

    We present a photon splatting technique which reduces noise and blur in the rendering of caustics. Blurring of illumination edges is an inherent problem in photon splatting, as each photon is unaware of its neighbours when being splatted. This means that the splat size is usually based on...... heuristics rather than knowledge of the local flux density. We use photon differentials to determine the size and shape of the splats such that we achieve adaptive anisotropic flux density estimation in photon splatting. As compared to previous work that uses photon differentials, we present the first method...... where no photons or beams or differentials need to be stored in a map. We also present improvements in the theory of photon differentials, which give more accurate results and a faster implementation. Our technique has good potential for GPU acceleration, and we limit the number of parameters requiring...

  16. Constructing And Rendering Vectorised Photographic Images

    Directory of Open Access Journals (Sweden)

    P. J. Willis

    2013-06-01

    Full Text Available We address the problem of representing captured images in the continuous mathematical space more usually associated with certain forms of drawn ('vector' images. Such an image is resolution-independent so can be used as a master for varying resolution-specific formats. We briefly describe the main features of a vectorising codec for photographic images, whose significance is that drawing programs can access images and image components as first-class vector objects. This paper focuses on the problem of rendering from the isochromic contour form of a vectorised image and demonstrates a new fill algorithm which could also be used in drawing generally. The fill method is described in terms of level set diffusion equations for clarity. Finally we show that image warping is both simplified and enhanced in the vector form and that we can demonstrate real histogram equalisation with genuinely rectangular histograms straightforwardly.

  17. Transgene Stacking in Cotton Improvement

    Institute of Scientific and Technical Information of China (English)

    2008-01-01

    To date,more and more transgenic varieties of upland cotton(Gossypium hirsutum L.) generated with transgenes,which derived from varies of alien species,are playing important role in agricultural production.Stacking of multi-transgenes has a potential for combining all the merits of distinct

  18. Rendering with mental ray and 3ds Max

    CERN Document Server

    van der Steen, Joep

    2009-01-01

    Create stunning renders of your 3ds Max models in mental ray with this concise guide. Learn all of the essential concepts such as indirect illumination, materials, render options, shaders, and lighting. Rendering with mental ray and 3ds Max, Second Edition is now revised to cover Autodesk Revit and special effects. The companion website includes all of the necessary project files from inside the book. *Render beautiful scenes with 3ds Max and the powerful mental ray application*Covers all aspects of rendering including materials, lighting, shaders, indirec

  19. Resolution-independent surface rendering using programmable graphics hardware

    Science.gov (United States)

    Loop, Charles T.; Blinn, James Frederick

    2008-12-16

    Surfaces defined by a Bezier tetrahedron, and in particular quadric surfaces, are rendered on programmable graphics hardware. Pixels are rendered through triangular sides of the tetrahedra and locations on the shapes, as well as surface normals for lighting evaluations, are computed using pixel shader computations. Additionally, vertex shaders are used to aid interpolation over a small number of values as input to the pixel shaders. Through this, rendering of the surfaces is performed independently of viewing resolution, allowing for advanced level-of-detail management. By individually rendering tetrahedrally-defined surfaces which together form complex shapes, the complex shapes can be rendered in their entirety.

  20. Transgenic Farm Animals

    Science.gov (United States)

    The development of recombinant DNA technology has enabled scientists to isolate single genes, analyze and modify their nucleotide structure(s), make copies of these isolated genes, and insert copies of these genes into the genome of plants and animals. The transgenic technology of adding genes to li...

  1. Efficient and Effective Volume Visualization with Enhanced Isosurface Rendering

    CERN Document Server

    Yang, Fei; Tian, Jie

    2012-01-01

    Compared with full volume rendering, isosurface rendering has several well recognized advantages in efficiency and accuracy. However, standard isosurface rendering has some limitations in effectiveness. First, it uses a monotone colored approach and can only visualize the geometry features of an isosurface. The lack of the capability to illustrate the material property and the internal structures behind an isosurface has been a big limitation of this method in applications. Another limitation of isosurface rendering is the difficulty to reveal physically meaningful structures, which are hidden in one or multiple isosurfaces. As such, the application requirements of extract and recombine structures of interest can not be implemented effectively with isosurface rendering. In this work, we develop an enhanced isosurface rendering technique to improve the effectiveness while maintaining the performance efficiency of the standard isosurface rendering. First, an isosurface color enhancement method is proposed to il...

  2. Post-transcriptional gene silencing signal could move rapidly and bidirectionally in grafted Arabidopsis thaliana

    Institute of Scientific and Technical Information of China (English)

    LI Ming; JIANG Shiling; WANG Youqun; LIU Guoqin

    2006-01-01

    RNA interference (RNAi), one of the newly found ways for post-transcriptional gene silencing, has been widely used to investigate gene functions through transgenic methods for introducing an RNA silencing signal into plants. In the present study, we constructed a dexamethazone (DEX)-inducible RNAi binary vector harboring a specific sequence fragment (168-bp) homologous to KatB and KatC, two kinesin isoform genes of Arabidopsis, which were proved to result in the post-transcriptional gene silencing of KatB and KatC in DEX-induced transgenic plants. RT-PCR and Northern blot analysis on transgenic homozygous Arabidopsis (termed as RNAi-type plants) showed that DEX inducement causes KatB and KatC mRNA degradation. With a simplified method, Arabidopsis grafting was effectively performed between RNAi-type and wild-type lines. The target gene mRNA levels were tested based on semi-quantitative RT-PCR. Our results demonstrateed that DEX-induced gene silencing signals could result in a reduction in KatB and KatC mRNA in the wild-type rootstocks or scions, indicating that silencing signals of RNAi could be transmitted bidirectionally across the graft junction whether RNAi-plants were scions or stocks. In contrast to the previously reported results on grafted tobacco, the transmission of post- transcriptional gene silencing signals caused by RNAi in grafted Arabidopsis is more effective than that in tobacco.

  3. Epidermal control of floral organ identity by class B homeotic genes in Antirrhinum and Arabidopsis.

    Science.gov (United States)

    Efremova, N; Perbal, M C; Yephremov, A; Hofmann, W A; Saedler, H; Schwarz-Sommer, Z

    2001-07-01

    To assess the contribution of the epidermis to the control of petal and stamen organ identity, we have used transgenic Antirrhinum and Arabidopsis plants that expressed the Antirrhinum class B homeotic transcription factors DEFICIENS (DEF) and GLOBOSA (GLO) in the epidermis. Transgene expression was controlled by the ANTIRRHINUM FIDDLEHEAD (AFI) promoter, which directs gene expression to the L1 meristematic layer and, later, to the epidermis of differentiating organs. Transgenic epidermal DEF and GLO chimeras display similar phenotypes, suggesting similar epidermal contributions by the two class B genes in ANTIRRHINUM: Epidermal B function autonomously controls the differentiation of Antirrhinum petal epidermal cell types, but cannot fully control the pattern of cell divisions and the specification of sub-epidermal petal cell-identity by epidermal signalling. This non-autonomous control is enhanced if the endogenous class B genes can be activated from the epidermis. The developmental influence of epidermal B function in Antirrhinum stamen development is very limited. In contrast, epidermal B function in Arabidopsis can control most if not all epidermal and sub-epidermal differentiation events in petals and stamens, without any contribution from the endogenous class B genes. Possible reasons for differences in the efficacy of B-function-mediated cell communication between the two species are discussed. Interestingly, our experiments uncovered partial incompatibility between class B functional homologues. Although the DEFICIENS/PISTILLATA heterodimer is functional in transgenic Arabidopsis plants, the APETALA3/GLOBOSA heterodimer is not. PMID:11526073

  4. Novel sulI binary vectors enable an inexpensive foliar selection method in Arabidopsis

    Directory of Open Access Journals (Sweden)

    Smith Jamison

    2011-03-01

    Full Text Available Abstract Background Sulfonamide resistance is conferred by the sulI gene found on many Enterobacteriaceae R plasmids and Tn21 type transposons. The sulI gene encodes a sulfonamide insensitive dihydropteroate synthase enzyme required for folate biosynthesis. Transformation of tobacco, potato or Arabidopsis using sulI as a selectable marker generates sulfadiazine-resistant plants. Typically sulI-based selection of transgenic plants is performed on tissue culture media under sterile conditions. Findings A set of novel binary vectors containing a sulI selectable marker expression cassette were constructed and used to generate transgenic Arabidopsis. We demonstrate that the sulI selectable marker can be utilized for direct selection of plants grown in soil with a simple foliar spray application procedure. A highly effective and inexpensive high throughput screening strategy to identify transgenic Arabidopsis without use of tissue culture was developed. Conclusion Novel sulI-containing Agrobacterium binary vectors designed to over-express a gene of interest or to characterize a test promoter in transgenic plants have been constructed. These new vector tools combined with the various beneficial attributes of sulfonamide selection and the simple foliar screening strategy provide an advantageous alternative for plant biotechnology researchers. The set of binary vectors is freely available upon request.

  5. The draft genome of the transgenic tropical fruit tree papaya ( Carica papaya Linnaeus)

    OpenAIRE

    Ming, Ray; Hou, Shaobin; Feng, Yun; Yu, Qinguyi; Thimmapuram, Jyothi

    2008-01-01

    Papaya, a fruit crop cultivated in tropical and subtropical regions, is known for its nutritional benefits and medicinal applications. Here we report a 3 draft genome sequence of 'SunUp' papaya, the first commercial virus-resistant transgenic fruit tree1 to be sequenced. The papaya genome is three times the size of the Arabidopsis genome, but contains fewer genes, including significantly fewer disease-resistance gene analogues. Comparison of the five sequenced genomes suggests a minimal angio...

  6. The draft genome of the transgenic tropical fruit tree papaya (Carica papaya Linnaeus)

    OpenAIRE

    Ming, Ray; Hou, Shaobin; Feng, Yun; Yu, Qingyi; Dionne-Laporte, Alexandre; Saw, Jimmy H.; Senin, Pavel; Wang, Wei; Ly, Benjamin V; Lewis, Kanako L. T.; Salzberg, Steven L.; Feng, Lu; Jones, Meghan R; Skelton, Rachel L; Murray, Jan E

    2008-01-01

    Papaya, a fruit crop cultivated in tropical and subtropical regions, is known for its nutritional benefits and medicinal applications. Here we report a 3× draft genome sequence of ‘SunUp’ papaya, the first commercial virus-resistant transgenic fruit tree1 to be sequenced. The papaya genome is three times the size of the Arabidopsis genome, but contains fewer genes, including significantly fewer disease-resistance gene analogues. Comparison of the five sequenced genomes suggests a minimal angi...

  7. Molecular screening tools to study Arabidopsis transcription factors

    Directory of Open Access Journals (Sweden)

    Nora eWehner

    2011-11-01

    Full Text Available In the model plant Arabidopsis thaliana, more than 2000 genes are estimated to encode transcription factors (TFs, which clearly emphasizes the importance of transcriptional control. Although genomic approaches have generated large TF Open Reading Frame (ORF collections, only a limited number of these genes is functionally characterized, yet. This review evaluates strategies and methods to identify TF functions. In particular, we focus on two recently developed TF screening platforms, which make use of publi-cally available GATEWAY® compatible ORF collections. (1 The Arabidopsis thaliana TF ORF over-Expression (AtTORF-Ex library provides pooled collections of transgenic lines over-expressing HA-tagged TF genes, which are suited for screening approaches to define TF functions in stress defense and development. (2 A high-throughput microtiter plate based Protoplast Trans Activation (PTA system has been established to screen for TFs which are regulating a given promoter:Luciferase construct in planta.

  8. Transgenic plants expressing the AaIT/GNA fusion protein show increased resistance and toxicity to both chewing and sucking pests.

    Science.gov (United States)

    Liu, Shu-Min; Li, Jie; Zhu, Jin-Qi; Wang, Xiao-Wei; Wang, Cheng-Shu; Liu, Shu-Sheng; Chen, Xue-Xin; Li, Sheng

    2016-04-01

    The adoption of pest-resistant transgenic plants to reduce yield losses and decrease pesticide use has been successful. To achieve the goal of controlling both chewing and sucking pests in a given transgenic plant, we generated transgenic tobacco, Arabidopsis, and rice plants expressing the fusion protein, AaIT/GNA, in which an insecticidal scorpion venom neurotoxin (Androctonus australis toxin, AaIT) is fused to snowdrop lectin (Galanthus nivalis agglutinin, GNA). Compared with transgenic tobacco and Arabidopsis plants expressing AaIT or GNA, transgenic plants expressing AaIT/GNA exhibited increased resistance and toxicity to one chewing pest, the cotton bollworm, Helicoverpa armigera. Transgenic tobacco and rice plants expressing AaIT/GNA showed increased resistance and toxicity to two sucking pests, the whitefly, Bemisia tabaci, and the rice brown planthopper, Nilaparvata lugens, respectively. Moreover, in the field, transgenic rice plants expressing AaIT/GNA exhibited a significant improvement in grain yield when infested with N. lugens. This study shows that expressing the AaIT/GNA fusion protein in transgenic plants can be a useful approach for controlling pests, particularly sucking pests which are not susceptible to the toxin in Bt crops. PMID:25641865

  9. Transgenics in crops

    Science.gov (United States)

    Li, Y.; Wu, Y. H.; McAvoy, R.; Duan, H.

    2001-01-01

    With rapid world population growth and declining availability of fresh water and arable land, a new technology is urgently needed to enhance agricultural productivity. Recent discoveries in the field of crop transgenics clearly demonstrate the great potential of this technology for increasing food production and improving food quality while preserving the environment for future generations. In this review, we briefly discuss some of the recent achievements in crop improvement that have been made using gene transfer technology.

  10. Retinoblastoma in transgenic mice

    OpenAIRE

    Windle, J J; Albert, D. M.; O'Brien, J. M.; Marcus, D. M.; Disteche, Ch.M.; Bernards, R.A.; Mellon, P L

    1990-01-01

    Retinoblastoma, a malignancy of the eye occurring in young children, has been widely studied as a model for genetic predisposition to cancer. This disease is caused by mutations in both alleles of an anti-oncogene (the retinoblastoma gene, Rb) that inactivate or eliminate the Rb encoded protein, pl05rb. Here we report that expression of a viral oncogene, the simian virus 40 T antigen, in the retina of transgenic mice produces heritable ocular tumours with histological, ultrastructural and imm...

  11. Direct send compositing for parallel sort-last rendering

    OpenAIRE

    Eilemann, S; Pajarola, R.

    2007-01-01

    In contrast to sort-first, sort-last parallel rendering has the distinct advantage that the task division for parallel geometry processing and rasterization is simple, and can easily be incorporated into most visualization systems. However, the efficient final depth-compositing for polygonal data, or alpha-blending for volume data of partial rendering results is the key to achieve scalability in sort-last parallel rendering. In this paper, we demonstrate the efficiency as well as ...

  12. Efficient and Effective Volume Visualization with Enhanced Isosurface Rendering

    OpenAIRE

    Yang, Fei; Cao, Yong; Tian, Jie

    2012-01-01

    Compared with full volume rendering, isosurface rendering has several well recognized advantages in efficiency and accuracy. However, standard isosurface rendering has some limitations in effectiveness. First, it uses a monotone colored approach and can only visualize the geometry features of an isosurface. The lack of the capability to illustrate the material property and the internal structures behind an isosurface has been a big limitation of this method in applications. Another limitation...

  13. Realistic Real-Time Rendering of Landscapes Using Billboard Clouds

    OpenAIRE

    Behrendt, Stephan; Colditz, Carsten; Franzke, Oliver; Kopf, Johannes; Deussen, Oliver

    2005-01-01

    We present techniques for realistic real-time rendering of complex landscapes that consist of many highly detailed plant models. The plants are approximated by dynamically changing sets of billboards. Realistic illumination is approximated using spherical harmonics. Since even the rendering of simple billboard cloud plants is too time consuming, the landscape in the background is approximated with shell textures. The combination of these techniques allows us to render large scenes in real-tim...

  14. Over-Expression of ScMnSOD, a SOD Gene Derived from Jojoba, Improve Drought Tolerance in Arabidopsis

    Institute of Scientific and Technical Information of China (English)

    LIU Xiao-fei; ZHANG Gen-fa; SUN Wei-min; LI Ze-qin; BAI Rui-xue; LI Jing-xiao; SHI Zi-han; GENG Hong-wei; ZHENG Ying; ZHANG Jun

    2013-01-01

    Jojoba (Simmondsia chinensis) is mainly distributed in desert, and the molecular mechanisms of jojoba in response to abiotic stress still remain elusive. In this paper, we cloned and characterized a SOD gene from jojoba named as ScMnSOD, and introduced into Arabidopsis to investigate its functions of responding to drought stress. The transgenic Arabidopsis showed an improvement in drought tolerance. Moreover, under a water deifcit condition, the accumulation of reactive oxygen species (ROS) was remarkably decreased in the transgenic lines compared to the WT. Furthermore, the ScMnSOD promoter was cloned to the 5´-upstream of GUS coding region in a binary vector, and introduced into Arabidopsis. And results showed that ScMnSOD expression can be induced by drought, salt, ABA, and low temperature. In conclusion, ScMnSOD plays an important role in drought tolerance which is, at least partially, attributed to its role in ROS detoxiifcation.

  15. Fast combinative volume rendering by indexed data structure

    Institute of Scientific and Technical Information of China (English)

    孙文武; 王文成; 吴恩华

    2001-01-01

    It is beneficial to study the interesting contents in a data set by combining and rendering variouscontents of the data. In this regard, an indexed data structure is proposed to facilitate the reorganization of data so that the contents of the data can be combined conveniently and only the selected contents in the data are processed for rendering. Based on the structure, the cells of different contents can be queued up easily so that the volume rendering can be conducted more accurately and quickly. Experimental results show that the indexed data structure is very efficient in improving combinative volume rendering.

  16. Beyond the Renderer: Software Architecture for Parallel Graphics and Visualization

    Science.gov (United States)

    Crockett, Thomas W.

    1996-01-01

    As numerous implementations have demonstrated, software-based parallel rendering is an effective way to obtain the needed computational power for a variety of challenging applications in computer graphics and scientific visualization. To fully realize their potential, however, parallel renderers need to be integrated into a complete environment for generating, manipulating, and delivering visual data. We examine the structure and components of such an environment, including the programming and user interfaces, rendering engines, and image delivery systems. We consider some of the constraints imposed by real-world applications and discuss the problems and issues involved in bringing parallel rendering out of the lab and into production.

  17. A Sort-Last Rendering System over an Optical Backplane

    OpenAIRE

    Yasuhiro Kirihata; Jason Leigh; Chaoyue Xiong; Tadao Murata

    2005-01-01

    Sort-Last is a computer graphics technique for rendering extremely large data sets on clusters of computers. Sort-Last works by dividing the data set into even-sized chunks for parallel rendering and then composing the images to form the final result. Since sort-last rendering requires the movement of large amounts of image data among cluster nodes, the network interconnecting the nodes becomes a major bottleneck. In this paper, we describe a sort-last rendering system implemented on a cluste...

  18. Expression of a High Mobility Group Protein Isolated from Cucumis sativus Affects the Germination of Arabidopsis thaliana under Abiotic Stress Conditions

    Institute of Scientific and Technical Information of China (English)

    Ji Young Jang; Kyung Jin Kwak; Hunseung Kang

    2008-01-01

    Although high mobility group B (HMGB) proteins have been identified from a variety of plant species, their importance and functional roles in plant responses to changing environmental conditions are largely unknown. Here, we investigated the functional roles of a CsHMGB isolated from cucumber (Cucurnis sativus L.) in plant responses to environmental stimuli. Under normal growth conditions or when subjected to cold stress, no differences in plant growth were found between the wild.type and transgenic Arabidopsis thaliana overexpressing CsHMGB. By contrast, the transgenic Arabidopsis plants displayed retarded germination compared with the wild-type plants when grown under high salt or dehydration stress conditions. Germination of the transgenic plants was delayed by the addition of abscisic acid (ABA), implying that CsHMGB affects germination through an ABA-dependent way. The expression of CsHMGB had affected only the germination stage, and CsHMGB did not affect the seedling growth of the transgenic plants under the stress conditions. The transcript levels of several germination-responsive genes were modulated by the expression of CsHMGB in Arabidopsis. Taken together, these results suggest that ectopic expression of a CsHMGB in Arabidopsis modulates the expression of several germination-responsive genes, and thereby affects the germination of Arabidopsis plants under different stress conditions.

  19. A reference map of the Arabidopsis thaliana mature pollen proteome

    International Nuclear Information System (INIS)

    The male gametophyte (or pollen) plays an obligatory role during sexual reproduction of higher plants. The extremely reduced complexity of this organ renders pollen a valuable experimental system for studying fundamental aspects of plant biology such as cell fate determination, cell-cell interactions, cell polarity, and tip-growth. Here, we present the first reference map of the mature pollen proteome of the dicotyledonous model plant species, Arabidopsis thaliana. Based on two-dimensional gel electrophoresis, matrix-assisted laser desorption/ionization time-of-flight, and electrospray quadrupole time-of-flight mass spectrometry, we reproducibly identified 121 different proteins in 145 individual spots. The presence, subcellular localization, and functional classification of the identified proteins are discussed in relation to the pollen transcriptome and the full protein complement encoded by the nuclear Arabidopsis genome

  20. Overexpression of OsWRKY72 gene interferes in the abscisic acid signal and auxin transport pathway of Arabidopsis

    Indian Academy of Sciences (India)

    Song Yu; Chen Ligang; Zhang Liping; Yu Diqiu

    2010-09-01

    Through activating specific transcriptional programmes, plants can launch resistance mechanisms to stressful environments and acquire a new equilibrium between development and defence. To screen the rice WRKY transcription factor which functions in abiotic stress tolerance and modulates the abscisic acid (ABA) response, we generated a whole array of 35S-OsWRKY transgenic Arabidopsis. In this study, we report that 35S-OsWRKY72 transgenic Arabidopsis, whose seed germination was retarded under normal conditions, emerged more sensitive to mannitol, NaCl, ABA stresses and sugar starvation than vector plants. Meanwhile, 35S-OsWRKY72 transgenic Arabidopsis displayed early flowering, reduced apical dominance, lost high temperature-induced hypocotyl elongation response, and enhanced gravitropism response, which were similar to the auxin-related gene mutants aux1, axr1 and bud1. Further, semi-quantitative RT-PCR showed that the expression patterns of three auxin-related genes AUX1, AXR1 and BUD1 were significantly altered in rosette leaves and inflorescences of 35S-OsWRKY72 plants compared with control Arabidopsis, and two ABA-related genes ABA2 and ABI4 were induced in 35S-OsWRKY72 seedlings. In addition, northern blot analysis indicated that, in rice, OsWRKY72 was inducible by polyethylene glycol (PEG), NaCl, naphthalene acetic acid (NAA), ABA and 42°C, similar to its orthologue AtWRKY75 in Arabidopsis, implying that these two WRKY genes might be required for multiple physiological processes in their plants. Together, these results suggest that OsWRKY72 interferes in the signal cross-talk between the ABA signal and auxin transport pathway in transgenic Arabidopsis.

  1. Transgenic algae engineered for higher performance

    Energy Technology Data Exchange (ETDEWEB)

    Unkefer, Pat J; Anderson, Penelope S; Knight, Thomas J

    2014-10-21

    The present disclosure relates to transgenic algae having increased growth characteristics, and methods of increasing growth characteristics of algae. In particular, the disclosure relates to transgenic algae comprising a glutamine phenylpyruvate transaminase transgene and to transgenic algae comprising a glutamine phenylpyruvate transaminase transgene and a glutamine synthetase.

  2. Leaf Downward Curvature and Delayed Flowering Caused by AtLH Overexpression in Arabidopsis thaliana

    Institute of Scientific and Technical Information of China (English)

    WUHao; YULin; TANGXiang-Rong; SHENRui-Juan; HEYu-Ke

    2004-01-01

    AtLHgene of Arabidopsis is a BcpLH(leafy head) homolog of Chinese cabbage, which encodes a double-stranded RNA-binding protein related to the curvature of folding leaf leading to the formation of leafy head. In order to elucidate the regulatory function of AtLH in the development of leaf curvature, we made a construct of 35S::AtLHand transformed it to Arabidopsis. In transgenic plants for sense-AtLH, transcripts of AtLH gene were increased significantly in leaves and flowers, giving rise to the AtLH-overexpressed plants in which the rosette leaves curved downward or outward in a manner of enhanced epinastic growth. Compared with normal plants, bolting and flowering time of the transgenic plants was significantly delayed. Moreover, the apical dominance of transgenic plants was weaker in vegetative shoots since more axillary shoots emerged from axil of rosette leaves, while stronger in flowering shoots because fewer cauline inflorescences were observed on the main inflorescence. In other aspects, these transgenic plants exhibited an increase in root-stimulating response to IAA and decrease in root-inhibitory reaction on ABA. It indicates that overexpression of AtLH causes downward curvature of transgenic plants.

  3. Transgenics, agroindustry and food sovereignty

    OpenAIRE

    Xavier Alejandro León Vega

    2014-01-01

    Food sovereignty has been implemented constitutionally in Ecuador; however, many of the actions and policies are designed to benefit the dominant model of food production, based in agroindustry, intensive monocultures, agrochemicals and transgenics. This article reflects upon the role of family farming as a generator of food sovereignty, and secondly the threat to them by agroindustry agriculture based in transgenic. The role played by food aid in the introduction of transgenic in Latin Ameri...

  4. Osmotic stress-regulated the expression of glutathione peroxidase 3 in Arabidopsis

    Institute of Scientific and Technical Information of China (English)

    MIAO YuChen; GUO JingGong; LIU ErTao; LI Kun; DAI Jie; WANG PengCheng; CHEN Jia; SONG ChunPeng

    2007-01-01

    Gene expression of glutathione peroxidase 3 (ATGPX3) in response to osmotic stress was analyzed in Arabidopsis using ATGPX3 promoter-glucuronidase (GUS) transgenic plants. High levels of GUS expression were detected under osmotic stress in ATGPX3 promoter-GUS transgenic plants. Compared with the wild type, the growth and development of ATGPX3 mutants (atgpx3-1) were more sensitive to mannitol. In addition, the expression of RD29A, ABI1, ABI2 and RbohD in atgpx3-1 was induced by ABA stress. These results suggest that ATGPX3 might be involved in the signal transduction of osmotic stress.

  5. Cryopreservation of Xenopus transgenic lines.

    Science.gov (United States)

    Buchholz, Daniel R; Fu, Liezhen; Shi, Yun-Bo

    2004-01-01

    Xenopus laevis has been widely used for molecular, cellular, and developmental studies. With the development of the sperm-mediated transgenic method, it is now possible to study gene function during vertebrate development by using this popular model. On the other hand, like other animal species, it is labor intensive, and the maintenance of transgenic lines is expensive. In this article, we investigated the possibility of using sperm-cryopreservation as a means to preserve transgenic frog lines. We demonstrated that cryopreserved sperms are viable but not fertile under our in vitro fertilization (IVF) conditions. However, by microinjecting cryopreserved sperm nuclei, we successfully regenerated a transgenic line carrying a double promoter transgene construct, where the marker gene encoding the green fluorescent protein (GFP) is driven by the gamma-crystallin gene promoter and a gene of interest, encoding a fusion protein of GFP with the matrix metalloproteinase stromelysin-3 (ST3-GFP), is driven by a heat shock-inducible promoter. We demonstrated the functional transmission of the ST3-GFP transgene by analyzing the phenotype of the F1 animals after heat-shock to induce its expression. Our method thus provides an inexpensive means to preserve transgenic frog lines and a convenient way for distribution of transgenic lines. Furthermore, the ease with which to microinject nuclei compared to the technically demanding transgenesis procedure with variable outcome should facilitate more laboratories to use transgenic Xenopus laevis for functional studies in vivo. Mol. Reprod. Dev. 67: 65-69, 2004. PMID:14648875

  6. Optimized iPhone Real-TimeRendering

    OpenAIRE

    Hellstrand, Peter

    2011-01-01

    Rendering is the process of generating an image from a model. This process requires heavy computations. The iPhone has very limited hardware. The purpose of this project is to optimize the rendering process in the iPhone game "Top Gear, Stunt School" developed by Resolution Interactive AB. This thesis describes the evaluation and implementation of different optimizations used for the game.

  7. 18 CFR 1308.17 - Failure to render timely decision.

    Science.gov (United States)

    2010-04-01

    ... 18 Conservation of Power and Water Resources 2 2010-04-01 2010-04-01 false Failure to render timely decision. 1308.17 Section 1308.17 Conservation of Power and Water Resources TENNESSEE VALLEY AUTHORITY CONTRACT DISPUTES Contracting Officers § 1308.17 Failure to render timely decision. Any failure...

  8. Method of producing hydrogen, and rendering a contaminated biomass inert

    Science.gov (United States)

    Bingham, Dennis N [Idaho Falls, ID; Klingler, Kerry M [Idaho Falls, ID; Wilding, Bruce M [Idaho Falls, ID

    2010-02-23

    A method for rendering a contaminated biomass inert includes providing a first composition, providing a second composition, reacting the first and second compositions together to form an alkaline hydroxide, providing a contaminated biomass feedstock and reacting the alkaline hydroxide with the contaminated biomass feedstock to render the contaminated biomass feedstock inert and further producing hydrogen gas, and a byproduct that includes the first composition.

  9. Media Presentation Synchronisation for Non-monolithic Rendering Architectures

    NARCIS (Netherlands)

    Vaishnavi, I.; Bulterman, D.C.A.; Cesar Garcia, P.S.; Gao, B.

    2007-01-01

    Non-monolithic renderers are physically distributed media playback engines. Non-monolithic renderers may use a number of different underlying network connection types to transmit media items belonging to a presentation. There is therefore a need for a media based and inter-network- type synchronizat

  10. Government scientists find new uses for rendered fat and protein

    Science.gov (United States)

    The rendering industry depends heavily on the utilization of their products in formulated animal feed; few other economically significant outlets for rendered fat and protein exist. The Fats Oils and Animal Coproducts Research Unit (FOAC), a group of scientists within the USDA’s Agricultural Resear...

  11. Research of global illumination algorithms rendering in glossy scene

    Institute of Scientific and Technical Information of China (English)

    BAI Shuangxue; ZHANG Qiang; ZHOU Dongsheng

    2012-01-01

    In computer graphic (CG), illumination rendering generated realistic effect at virtual scene is amazing. Not only plausible lighting effect is to show the relative position between of the objects, but also to reflect the material of visual appearance of the vir- tual objects. The diffuse-scene rendering reflectance credibility has gradually matured. Global illumination rendering method for the glossy material is still a challenge for the CG research. Because of the shiny materials is highly energy reflection between the com- plex light paths. Whether we trace glossy reflection paths, or use of one-reflection or multi-reflection approximate above complex il- lumination transmission is a difficult working. This paper we gather some commonly used global illumination algorithms recently year and its extension glossy scene improvements. And we introduce the limitation of classical algorithms rendering glossy scene and some extended solution. Finally, we will summarize the illumination rendering for specular scene, there are still some open prob- lems.

  12. A Volume Rendering Algorithm for Sequential 2D Medical Images

    Institute of Scientific and Technical Information of China (English)

    吕忆松; 陈亚珠

    2002-01-01

    Volume rendering of 3D data sets composed of sequential 2D medical images has become an important branch in image processing and computer graphics.To help physicians fully understand deep-seated human organs and focuses(e.g.a tumour)as 3D structures.in this paper,we present a modified volume rendering algorithm to render volumetric data,Using this method.the projection images of structures of interest from different viewing directions can be obtained satisfactorily.By rotating the light source and the observer eyepoint,this method avoids rotates the whole volumetric data in main memory and thus reduces computational complexity and rendering time.Experiments on CT images suggest that the proposed method is useful and efficient for rendering 3D data sets.

  13. Effects of display rendering on HDR image quality assessment

    Science.gov (United States)

    Zerman, Emin; Valenzise, Giuseppe; De Simone, Francesca; Banterle, Francesco; Dufaux, Frederic

    2015-09-01

    High dynamic range (HDR) displays use local backlight modulation to produce both high brightness levels and large contrast ratios. Thus, the display rendering algorithm and its parameters may greatly affect HDR visual experience. In this paper, we analyze the impact of display rendering on perceived quality for a specific display (SIM2 HDR47) and for a popular application scenario, i.e., HDR image compression. To this end, we assess whether significant differences exist between subjective quality of compressed images, when these are displayed using either the built-in rendering of the display, or a rendering algorithm developed by ourselves. As a second contribution of this paper, we investigate whether the possibility to estimate the true pixel-wise luminance emitted by the display, offered by our rendering approach, can improve the performance of HDR objective quality metrics that require true pixel-wise luminance as input.

  14. Abiotic and biotic stress tolerance in Arabidopsis overexpressing the multiprotein bridging factor 1a (MBF1a) transcriptional coactivator gene.

    Science.gov (United States)

    Kim, Min-Jung; Lim, Gah-Hyun; Kim, Eun-Seon; Ko, Chang-Beom; Yang, Kwang-Yeol; Jeong, Jin-An; Lee, Myung-Chul; Kim, Cheol Soo

    2007-03-01

    We conducted a genetic yeast screen to identify salt tolerance (SAT) genes in a maize kernel cDNA library. During the screening, we identified a maize clone (SAT41) that seemed to confer elevated salt tolerance in comparison to control cells. SAT41 cDNA encodes a 16-kDa protein which is 82.4% identical to the Arabidopsis Multiprotein bridging factor 1a (MBF1a) transcriptional coactivator gene. To further examine salinity tolerance in Arabidopsis, we functionally characterized the MBF1a gene and found that dehydration as well as heightened glucose (Glc) induced MBF1a expression. Constitutive expression of MBF1a in Arabidopsis led to elevated salt tolerance in transgenic lines. Interestingly, plants overexpressing MBF1a exhibited insensitivity to Glc and resistance to fungal disease. Our results suggest that MBF1a is involved in stress tolerance as well as in ethylene and Glc signaling in Arabidopsis. PMID:17234157

  15. The impact of altered herbicide residues in transgenic herbicide-resistant crops on standard setting for herbicide residues

    NARCIS (Netherlands)

    Kleter, G.A.; Unsworth, J.B.; Harris, C.A.

    2011-01-01

    The global area covered with transgenic (genetically modified) crops has rapidly increased since their introduction in the mid-1990s. Most of these crops have been rendered herbicide resistant, for which it can be envisaged that the modification has an impact on the profile and level of herbicide re

  16. Overexpression of VOZ2 confers biotic stress tolerance but decreases abiotic stress resistance in Arabidopsis

    OpenAIRE

    Nakai, Yusuke; Fujiwara, Sumire; Kubo, Yasuyuki; Sato, Masa H.

    2013-01-01

    VOZ (vascular plant one zinc-finger protein) is a plant specific one-zinc finger type transcriptional activator, which is highly conserved through land plant evolution. We have previously shown that loss-of-function mutations in VOZ1 and VOZ2 showed increased cold and drought stress tolerances whereas decreased biotic stress resistance in Arabidopsis. Here, we demonstrate that transgenic plants overexpressing VOZ2 impairs freezing and drought stress tolerances but increases resistance to a fu...

  17. The Arabidopsis NPR1 gene confers broad-spectrum disease resistance in strawberry.

    Science.gov (United States)

    Silva, Katchen Julliany P; Brunings, Asha; Peres, Natalia A; Mou, Zhonglin; Folta, Kevin M

    2015-08-01

    Although strawberry is an economically important fruit crop worldwide, production of strawberry is limited by its susceptibility to a wide range of pathogens and the lack of major commercial cultivars with high levels of resistance to multiple pathogens. The objective of this study is to ectopically express the Arabidopsis thaliana NPR1 gene (AtNPR1) in the diploid strawberry Fragaria vesca L. and to test transgenic plants for disease resistance. AtNPR1 is a key positive regulator of the long-lasting broad-spectrum resistance known as systemic acquired resistance (SAR) and has been shown to confer resistance to a number of pathogens when overexpressed in Arabidopsis or ectopically expressed in several crop species. We show that ectopic expression of AtNPR1 in strawberry increases resistance to anthracnose, powdery mildew, and angular leaf spot, which are caused by different fungal or bacterial pathogens. The increased resistance is related to the relative expression levels of AtNPR1 in the transgenic plants. In contrast to Arabidopsis plants overexpressing AtNPR1, which grow normally and do not constitutively express defense genes, the strawberry transgenic plants are shorter than non-transformed controls, and most of them fail to produce runners and fruits. Consistently, most of the transgenic lines constitutively express the defense gene FvPR5, suggesting that the SAR activation mechanisms in strawberry and Arabidopsis are different. Nevertheless, our results indicate that overexpression of AtNPR1 holds the potential for generation of broad-spectrum disease resistance in strawberry. PMID:25812515

  18. Ectopic Expression of an Activated RAC in Arabidopsis Disrupts Membrane CyclingD⃞V⃞

    OpenAIRE

    Bloch, Daria; Lavy, Meirav; Efrat, Yael; Efroni, Idan; Bracha-Drori, Keren; Abu-Abied, Mohamad; Sadot, Einat; Yalovsky, Shaul

    2005-01-01

    Rho GTPases regulate the actin cytoskeleton, exocytosis, endocytosis, and other signaling cascades. Rhos are subdivided into four subfamilies designated Rho, Racs, Cdc42, and a plant-specific group designated RACs/Rops. This research demonstrates that ectopic expression of a constitutive active Arabidopsis RAC, AtRAC10, disrupts actin cytoskeleton organization and membrane cycling. We created transgenic plants expressing either wild-type or constitutive active AtRAC10 fused to the green fluor...

  19. An auxin responsive CLE gene regulates shoot apical meristem development in Arabidopsis.

    Science.gov (United States)

    Guo, Hongyan; Zhang, Wei; Tian, Hainan; Zheng, Kaijie; Dai, Xuemei; Liu, Shanda; Hu, Qingnan; Wang, Xianling; Liu, Bao; Wang, Shucai

    2015-01-01

    Plant hormone auxin regulates most, if not all aspects of plant growth and development, including lateral root formation, organ pattering, apical dominance, and tropisms. Peptide hormones are peptides with hormone activities. Some of the functions of peptide hormones in regulating plant growth and development are similar to that of auxin, however, the relationship between auxin and peptide hormones remains largely unknown. Here we report the identification of OsCLE48, a rice (Oryza sativa) CLE (CLAVATA3/ENDOSPERM SURROUNDING REGION) gene, as an auxin response gene, and the functional characterization of OsCLE48 in Arabidopsis and rice. OsCLE48 encodes a CLE peptide hormone that is similar to Arabidopsis CLEs. RT-PCR analysis showed that OsCLE48 was induced by exogenously application of IAA (indole-3-acetic acid), a naturally occurred auxin. Expression of integrated OsCLE48p:GUS reporter gene in transgenic Arabidopsis plants was also induced by exogenously IAA treatment. These results indicate that OsCLE48 is an auxin responsive gene. Histochemical staining showed that GUS activity was detected in all the tissue and organs of the OsCLE48p:GUS transgenic Arabidopsis plants. Expression of OsCLE48 under the control of the 35S promoter in Arabidopsis inhibited shoot apical meristem development. Expression of OsCLE48 under the control of the CLV3 native regulatory elements almost completely complemented clv3-2 mutant phenotypes, suggesting that OsCLE48 is functionally similar to CLV3. On the other hand, expression of OsCLE48 under the control of the 35S promoter in Arabidopsis has little, if any effects on root apical meristem development, and transgenic rice plants overexpressing OsCLE48 are morphologically indistinguishable from wild type plants, suggesting that the functions of some CLE peptides may not be fully conserved in Arabidopsis and rice. Taken together, our results showed that OsCLE48 is an auxin responsive peptide hormone gene, and it regulates shoot apical

  20. Arabidopsis Hormone Database: a comprehensive genetic and phenotypic information database for plant hormone research in Arabidopsis.

    Science.gov (United States)

    Peng, Zhi-yu; Zhou, Xin; Li, Linchuan; Yu, Xiangchun; Li, Hongjiang; Jiang, Zhiqiang; Cao, Guangyu; Bai, Mingyi; Wang, Xingchun; Jiang, Caifu; Lu, Haibin; Hou, Xianhui; Qu, Lijia; Wang, Zhiyong; Zuo, Jianru; Fu, Xiangdong; Su, Zhen; Li, Songgang; Guo, Hongwei

    2009-01-01

    Plant hormones are small organic molecules that influence almost every aspect of plant growth and development. Genetic and molecular studies have revealed a large number of genes that are involved in responses to numerous plant hormones, including auxin, gibberellin, cytokinin, abscisic acid, ethylene, jasmonic acid, salicylic acid, and brassinosteroid. Here, we develop an Arabidopsis hormone database, which aims to provide a systematic and comprehensive view of genes participating in plant hormonal regulation, as well as morphological phenotypes controlled by plant hormones. Based on data from mutant studies, transgenic analysis and gene ontology (GO) annotation, we have identified a total of 1026 genes in the Arabidopsis genome that participate in plant hormone functions. Meanwhile, a phenotype ontology is developed to precisely describe myriad hormone-regulated morphological processes with standardized vocabularies. A web interface (http://ahd.cbi.pku.edu.cn) would allow users to quickly get access to information about these hormone-related genes, including sequences, functional category, mutant information, phenotypic description, microarray data and linked publications. Several applications of this database in studying plant hormonal regulation and hormone cross-talk will be presented and discussed. PMID:19015126

  1. Hardware Assisted Fast Volume Rendering with Boundary Enhancement

    Institute of Scientific and Technical Information of China (English)

    童欣; 唐泽圣

    1998-01-01

    In this paper,a new volume rendering method with boundary enhancement is presented.The boundary is extracted and represented by surfaces explicitly,Then,using 3D texture mapping and graphics acceleation hardware,the volume data can be rendered with controllable boundary shading effect almost in real time.Test shows that this method is 4-5 times faster than the previous methods.Moreover,it can also be extended to render the surfaces and the volumetric data together interactively.

  2. Local and Global Illumination in the Volume Rendering Integral

    OpenAIRE

    Max, Nelson; Chen, Min

    2010-01-01

    This article is intended as an update of the major survey by Max [Max, "Optical models for direct volume rendering.", IEEE Trans. on Visualization and Computer Graphics, 1(2):99–108, 1995] on optical models for direct volume rendering. It provides a brief overview of the subject scope covered by [Max, "Optical models for direct volume rendering.", IEEE Trans. on Visualization and Computer Graphics, 1(2):99–108, 1995], and brings recent developments, such as new shadow algorithms and refractio...

  3. Anisotropic 3D texture synthesis with application to volume rendering

    DEFF Research Database (Denmark)

    Laursen, Lasse Farnung; Ersbøll, Bjarne Kjær; Bærentzen, Jakob Andreas

    We present a novel approach to improving volume rendering by using synthesized textures in combination with a custom transfer function. First, we use existing knowledge to synthesize anisotropic solid textures to fit our volumetric data. As input to the synthesis method, we acquire high quality...... images using a 12.1 megapixel camera. Next, we extend the volume rendering pipeline by creating a transfer function which yields not only color and opacity from the input intensity, but also texture coordinates for our synthesized 3D texture. Thus, we add texture to the volume rendered images. This...

  4. ABA inducible rice protein phosphatase 2C confers ABA insensitivity and abiotic stress tolerance in Arabidopsis.

    Directory of Open Access Journals (Sweden)

    Amarjeet Singh

    Full Text Available Arabidopsis PP2C belonging to group A have been extensively worked out and known to negatively regulate ABA signaling. However, rice (Oryza sativa orthologs of Arabidopsis group A PP2C are scarcely characterized functionally. We have identified a group A PP2C from rice (OsPP108, which is highly inducible under ABA, salt and drought stresses and localized predominantly in the nucleus. Genetic analysis revealed that Arabidopsis plants overexpressing OsPP108 are highly insensitive to ABA and tolerant to high salt and mannitol stresses during seed germination, root growth and overall seedling growth. At adult stage, OsPP108 overexpression leads to high tolerance to salt, mannitol and drought stresses with far better physiological parameters such as water loss, fresh weight, chlorophyll content and photosynthetic potential (Fv/Fm in transgenic Arabidopsis plants. Expression profile of various stress marker genes in OsPP108 overexpressing plants revealed interplay of ABA dependent and independent pathway for abiotic stress tolerance. Overall, this study has identified a potential rice group A PP2C, which regulates ABA signaling negatively and abiotic stress signaling positively. Transgenic rice plants overexpressing this gene might provide an answer to the problem of low crop yield and productivity during adverse environmental conditions.

  5. ABA inducible rice protein phosphatase 2C confers ABA insensitivity and abiotic stress tolerance in Arabidopsis.

    Science.gov (United States)

    Singh, Amarjeet; Jha, Saroj K; Bagri, Jayram; Pandey, Girdhar K

    2015-01-01

    Arabidopsis PP2C belonging to group A have been extensively worked out and known to negatively regulate ABA signaling. However, rice (Oryza sativa) orthologs of Arabidopsis group A PP2C are scarcely characterized functionally. We have identified a group A PP2C from rice (OsPP108), which is highly inducible under ABA, salt and drought stresses and localized predominantly in the nucleus. Genetic analysis revealed that Arabidopsis plants overexpressing OsPP108 are highly insensitive to ABA and tolerant to high salt and mannitol stresses during seed germination, root growth and overall seedling growth. At adult stage, OsPP108 overexpression leads to high tolerance to salt, mannitol and drought stresses with far better physiological parameters such as water loss, fresh weight, chlorophyll content and photosynthetic potential (Fv/Fm) in transgenic Arabidopsis plants. Expression profile of various stress marker genes in OsPP108 overexpressing plants revealed interplay of ABA dependent and independent pathway for abiotic stress tolerance. Overall, this study has identified a potential rice group A PP2C, which regulates ABA signaling negatively and abiotic stress signaling positively. Transgenic rice plants overexpressing this gene might provide an answer to the problem of low crop yield and productivity during adverse environmental conditions. PMID:25886365

  6. Peroxidase-dependent apoplastic oxidative burst in Arabidopsis required for pathogen resistance.

    Science.gov (United States)

    Bindschedler, Laurence V; Dewdney, Julia; Blee, Kris A; Stone, Julie M; Asai, Tsuneaki; Plotnikov, Julia; Denoux, Carine; Hayes, Tezni; Gerrish, Chris; Davies, Dewi R; Ausubel, Frederick M; Bolwell, G Paul

    2006-09-01

    The oxidative burst is an early response to pathogen attack leading to the production of reactive oxygen species (ROS) including hydrogen peroxide. Two major mechanisms involving either NADPH oxidases or peroxidases that may exist singly or in combination in different plant species have been proposed for the generation of ROS. We identified an Arabidopsis thaliana azide-sensitive but diphenylene iodonium-insensitive apoplastic oxidative burst that generates H(2)O(2) in response to a Fusarium oxysporum cell-wall preparation. Transgenic Arabidopsis plants expressing an anti-sense cDNA encoding a type III peroxidase, French bean peroxidase type 1 (FBP1) exhibited an impaired oxidative burst and were more susceptible than wild-type plants to both fungal and bacterial pathogens. Transcriptional profiling and RT-PCR analysis showed that the anti-sense (FBP1) transgenic plants had reduced levels of specific peroxidase-encoding mRNAs, including mRNAs corresponding to Arabidopsis genes At3g49120 (AtPCb) and At3g49110 (AtPCa) that encode two class III peroxidases with a high degree of homology to FBP1. These data indicate that peroxidases play a significant role in generating H(2)O(2) during the Arabidopsis defense response and in conferring resistance to a wide range of pathogens. PMID:16889645

  7. TL transgenic mouse strains

    International Nuclear Information System (INIS)

    As a result of abnormal development of the thymus of these mice, TCR αβ lineage of the T cell differentiation is disturbed and cells belonging to the TCR γδ CD4- CD8- double negative (DN) lineage become preponderant. The γδ DN cells migrate into peripheral lymphoid organs and constitute nearly 50% of peripheral T cells. Immune function of the transgenic mice is severely impaired, indicating that the γδ cells are incapable of participating in these reactions. Molecular and serological analyses of T-cell lymphomas reveal that they belong to the γδ lineage. Tg.Tlaa-3-1 mice should be useful in defining the role of TL in normal and abnormal T cell differentiation as well as in the development of T-cell lymphomas, and further they should facilitate studies on the differentiation and function of γδ T cells. We isolated T3b-TL gene from B6 mice and constructed a chimeric gene in which T3b-TL is driven by the promoter of H-2Kb. With the chimeric gene, two transgenic mouse strains, Tg. Con.3-1 and -2 have been derived in C3H background. Both strains express TL antigen in various tissues including skin. The skin graft of transgenic mice on C3H and (B6 X C3H)F1 mice were rejected. In the mice which rejected the grafts, CD8+TCRαβ cytotoxic T cells (CTL) against TL antigens were recognized. The recognition of TL by CTL did not require the antigen presentation by H-2 molecules. The results indicated that TL antigen in the skin becomes a transplantation antigen and behaves like a typical allogeneic MHC class I antigen. The facts that (B6 X C3H)F1 mice rejected the skin expressing T3b-TL antigen and induced CTL that killed TL+ lymphomas of B6 origin revealed that TL antigen encoded by T3b-TL is recognized as non-self in B6 mice. Experiments are now extended to analyze immune responses to TL antigen expressed on autochthonous T cell lymphomas. (J.P.N.)

  8. [Transgenics without Manichaeism].

    Science.gov (United States)

    Valle, S

    2000-01-01

    We live in an era characterized by the hegemony of science and technology, an era fraught with questions awaiting answers which would enable a safe and sustainable future for humankind. The development of agro-industrial processes - food products in particular - through recombinant DNA technology has enhanced the profit prospects of the few big biotechnology companies and of large-scale farmers who have access to the latest technological developments. We thus oppose a moratorium on recombinant DNA technology. Moreover, hasty statements about risk-free transgenics may be misleading in the absence of extensive safety tests. There is a pressing need for the establishment of biosafety policy in this country involving the organized civil society and every government agency responsible for monitoring such matters. There is also the need to put in place a bio-surveillance and a code of ethics regarding genetic manipulation. PMID:16680900

  9. Arabidopsis in Wageningen

    OpenAIRE

    Koornneef, M

    2013-01-01

    Arabidopsis thaliana is the plant species that in the past 25 years has developed into the major model species in plant biology research. This was due to its properties such as short generation time, its small genome and its easiness to be transformed. Wageningen University has played an important role in the development of this model, based on interdisciplinary collaborations using genetics as a major tool to investigate aspects of physiology, development, plant-microbe interactions and evol...

  10. Partitioning of biocides between water and inorganic phases of render

    DEFF Research Database (Denmark)

    Urbanczyk, Michal; Bollmann, Ulla E.; Bester, Kai

    , the partitioning of biocides between water and inorganic phases of render was studied. In this study the partitioning constants of benzoisothiazolinone, carbendazim, dichlorooctylisothiazolinone, diuron, iodocarb, isoproturon, irgarol, mecoprop, methylisothiazolinone, octylisothiazolinone, terbutryn...

  11. Hybrid fur rendering: combining volumetric fur with explicit hair strands

    DEFF Research Database (Denmark)

    Andersen, Tobias Grønbeck; Falster, Viggo; Frisvad, Jeppe Revall;

    2016-01-01

    Hair is typically modeled and rendered using either explicitly defined hair strand geometry or a volume texture of hair densities. Taken each on their own, these two hair representations have difficulties in the case of animal fur as it consists of very dense and thin undercoat hairs in combination...... with coarse guard hairs. Explicit hair strand geometry is not well-suited for the undercoat hairs, while volume textures are not well-suited for the guard hairs. To efficiently model and render both guard hairs and undercoat hairs, we present a hybrid technique that combines rasterization of explicitly...... appearance as compared with renderings that only use explicitly defined hair strands. Finally, our rasterization approach is based on order-independent transparency and renders high-quality fur images in seconds....

  12. Interactive Depth-of-Field Rendering with Secondary Rays

    Institute of Scientific and Technical Information of China (English)

    Guo-Fu Xie; Xin Sun; Wen-Cheng Wang

    2013-01-01

    This paper presents an efficient method to trace secondary rays in depth-of-field (DOF) rendering,which significantly enhances realism.Till now,the effects by secondary rays have been little addressed in real-time/interactive DOF rendering,because secondary rays have less coherence than primary rays,making them very difficult to handle.We propose novel measures to cluster secondary rays,and take a virtual viewpoint to construct a layered image-based representation for the objects that would be intersected by a cluster of secondary rays respectively.Therefore,we can exploit coherence of secondary rays in the clusters to speed up tracing secondary rays in DOF rendering.Results show that we can interactively achieve DOF rendering effects with reflections or refractions on a commodity graphics card.

  13. GPU-accelerated volume rendering to 3D lenticular displays

    OpenAIRE

    Ruijters, Daniel

    2006-01-01

    Ruijters D., ''GPU-accelerated volume rendering to 3D lenticular displays'', Proceedings IEEE workshop on content generation and coding for 3D-television, IEEE Benelux chapter on consumer electronics, 3 pp., June 2, 2006, Eindhoven, The Netherlands.

  14. Multiresolution maximum intensity volume rendering by morphological adjunction pyramids

    NARCIS (Netherlands)

    Roerdink, Jos B.T.M.

    2003-01-01

    We describe a multiresolution extension to maximum intensity projection (MIP) volume rendering, allowing progressive refinement and perfect reconstruction. The method makes use of morphological adjunction pyramids. The pyramidal analysis and synthesis operators are composed of morphological 3-D eros

  15. Ectopically expressed sweet pepper ferredoxin PFLP enhances disease resistance to Pectobacterium carotovorum subsp. carotovorum affected by harpin and protease-mediated hypersensitive response in Arabidopsis.

    Science.gov (United States)

    Ger, Mang-Jye; Louh, Guan-Yu; Lin, Yi-Hsien; Feng, Teng-Yung; Huang, Hsiang-En

    2014-12-01

    Plant ferredoxin-like protein (PFLP) is a photosynthesis-type ferredoxin (Fd) found in sweet pepper. It contains an iron-sulphur cluster that receives and delivers electrons between enzymes involved in many fundamental metabolic processes. It has been demonstrated that transgenic plants overexpressing PFLP show a high resistance to many bacterial pathogens, although the mechanism remains unclear. In this investigation, the PFLP gene was transferred into Arabidopsis and its defective derivatives, such as npr1 (nonexpresser of pathogenesis-related gene 1) and eds1 (enhanced disease susceptibility 1) mutants and NAHG-transgenic plants. These transgenic plants were then infected with the soft-rot bacterial pathogen Pectobacterium carotovorum subsp. carotovorum (Erwinia carotovora ssp. carotovora, ECC) to investigate the mechanism behind PFLP-mediated resistance. The results revealed that, instead of showing soft-rot symptoms, ECC activated hypersensitive response (HR)-associated events, such as the accumulation of hydrogen peroxide (H2 O2 ), electrical conductivity leakage and expression of the HR marker genes (ATHSR2 and ATHSR3) in PFLP-transgenic Arabidopsis. This PFLP-mediated resistance could be abolished by inhibitors, such as diphenylene iodonium (DPI), 1-l-trans-epoxysuccinyl-leucylamido-(4-guanidino)-butane (E64) and benzyloxycarbonyl-Val-Ala-Asp-fluoromethylketone (z-VAD-fmk), but not by myriocin and fumonisin. The PFLP-transgenic plants were resistant to ECC, but not to its harpin mutant strain ECCAC5082. In the npr1 mutant and NAHG-transgenic Arabidopsis, but not in the eds1 mutant, overexpression of the PFLP gene increased resistance to ECC. Based on these results, we suggest that transgenic Arabidopsis contains high levels of ectopic PFLP; this may lead to the recognition of the harpin and to the activation of the HR and other resistance mechanisms, and is dependent on the protease-mediated pathway. PMID:24796566

  16. Epigenetic history of an Arabidopsis trans-silencer locus and a test for relay of trans-silencing activity

    Directory of Open Access Journals (Sweden)

    von Arnim Albrecht G

    2002-12-01

    Full Text Available Abstract Background Meiotically heritable epimutations affecting transgene expression are not well understood, even and in particular in the plant model species, Arabidopsis thaliana. The Arabidopsis trans-silencer locus, C73, which encodes a fusion protein between the repressor of photomorphogenesis, COP1, and green fluorescent protein (GFP-COP1, heritably modifies the expression pattern and cop1-like cosuppression phenotypes of multiple GFP-COP1 target loci by transcriptional gene silencing. Results Here we describe three additional features of trans-silencing by the C73 locus. First, the silencing phenotype of C73 and of similar complex loci was acquired epigenetically over the course of no more than two plant generations via a stage resembling posttranscriptional silencing. Second, imprints imposed by the C73 locus were maintained heritably for at least five generations in the absence of the silencer with only sporadic spontaneous reversion. Third, the pairing of two other GFP-COP1 transgene loci, L91 and E82, showed an increased tendency for epigenetic modification when L91 carried an epigenetic imprint from C73, but not when E82 bore the imprint. Conclusions The latter data suggest a transfer of trans-silencing activity from one transgene locus, C73, to another, namely L91. These results extend our operational understanding of interactions among transgenes in Arabidopsis.

  17. Sorting and hardware assisted rendering for volume visualization

    Energy Technology Data Exchange (ETDEWEB)

    Stein, C.; Becker, B.; Max, N.

    1994-03-01

    We present some techniques for volume rendering unstructured data. Interpolation between vertex colors and opacities is performed using hardware assisted texture mapping, and color is integrated for use with a volume rendering system. We also present an O(n{sup 2}) method for sorting n arbitrarily shaped convex polyhedra prior to visualization. It generalizes the Newell, Newell and Sancha sort for polygons to 3-D volume elements.

  18. User-guided scene stylization using efficient rendering techniques

    OpenAIRE

    Klehm, Oliver

    2015-01-01

    In this dissertation, we propose new techniques to display and manipulate virtual worlds to support visual design. The real-time constraint of applications such as games limits the accuracy at which rendering algorithms can simulate light transport. Our first method focuses on the efficient rendering of surfaces under natural illumination, extending previous work that ignores directionally-dependent effects in the lighting. In a second work, we present an approach for the efficient computatio...

  19. Wavelet subdivision methods gems for rendering curves and surfaces

    CERN Document Server

    Chui, Charles

    2010-01-01

    OVERVIEW Curve representation and drawing Free-form parametric curves From subdivision to basis functions Wavelet subdivision and editing Surface subdivision BASIS FUNCTIONS FOR CURVE REPRESENTATION Refinability and scaling functions Generation of smooth basis functions Cardinal B-splines Stable bases for integer-shift spaces Splines and polynomial reproduction CURVE SUBDIVISION SCHEMES Subdivision matrices and stencils B-spline subdivision schemes Closed curve rendering Open curve rendering BASIS FUNCTIONS GENERATED BY SUBDIVISION MATRICES Subdivision operators The up-sampling convolution ope

  20. Anisotropic 3D texture synthesis with application to volume rendering

    OpenAIRE

    Laursen, Lasse Farnung; Ersbøll, Bjarne Kjær; Bærentzen, Jakob Andreas

    2011-01-01

    We present a novel approach to improving volume rendering by using synthesized textures in combination with a custom transfer function. First, we use existing knowledge to synthesize anisotropic solid textures to fit our volumetric data. As input to the synthesis method, we acquire high quality images using a 12.1 megapixel camera. Next, we extend the volume rendering pipeline by creating a transfer function which yields not only color and opacity from the input intensity, but also texture co...

  1. Multidimensional Transfer Functions in Volume Rendering of Medical Datasets

    OpenAIRE

    2006-01-01

    In volume rendering, transfer functions are used to map voxel property into color and opacity. The most common voxel property used in transfer functions is the voxel intensity. Multiple voxel properties can also be used, and we then get a multidimensional transfer function. In this thesis, we want to test how well a two-dimensional transfer function performs, compared to a transfer function of just one dimension. To test this, we have implemented a fast volume rendering application using G...

  2. High Performance GPU-Based Fourier Volume Rendering

    OpenAIRE

    Marwan Abdellah; Ayman Eldeib; Amr Sharawi

    2015-01-01

    Fourier volume rendering (FVR) is a significant visualization technique that has been used widely in digital radiography. As a result of its (N 2log⁡N) time complexity, it provides a faster alternative to spatial domain volume rendering algorithms that are (N 3) computationally complex. Relying on the Fourier projection-slice theorem, this technique operates on the spectral representation of a 3D volume instead of processing its spatial representation to generate attenuation-only projection...

  3. User Interface for Volume Rendering in Virtual Reality Environments

    OpenAIRE

    Klein, Jonathan; Reuling, Dennis; Grimm, Jan; Pfau, Andreas; Lefloch, Damien; Lambers, Martin; Kolb, Andreas

    2013-01-01

    Volume Rendering applications require sophisticated user interaction for the definition and refinement of transfer functions. Traditional 2D desktop user interface elements have been developed to solve this task, but such concepts do not map well to the interaction devices available in Virtual Reality environments. In this paper, we propose an intuitive user interface for Volume Rendering specifically designed for Virtual Reality environments. The proposed interface allows transfer function d...

  4. Planet Rendering Using Online High-Resolution Datasets

    OpenAIRE

    Östergaard, Johan

    2008-01-01

    A large amount of image datasets are publicly available online through the web map service standard. The contents of the datasets span from satellite imagery of the earth and other planets of our solar system to various scientific data. This thesis presents an implementation of a planet renderer streaming high resolution image and height data from online datasets. The planet renderer uses a level of detail technique based on nodes connected by a quad tree data structure. The level of detail i...

  5. COMPARISON TRANSGENIC AND NON-TRANSGENIC MILK QUALITY

    Directory of Open Access Journals (Sweden)

    Peter Chrenek

    2012-02-01

    Full Text Available Transgenic founder rabbits carrying a gene construct consisting of a 2.5 kb murine whey acidic protein promoter (mWAP, 7.2 kb of the human clotting factor VIII (hFVIII cDNA and 4.6 kb of 3’ flanking sequences of mWAP gene were crossed for five generations. Transgenic females showed high level of recombinant hFVIII (rhFVIII mRNA expression in biopsed mammary gland tissues. The presence of the mWAP-hFVIII transgene in rabbit genome and secretion of rhFVIII into milk of transgenic females (F1, F2, F3, F4 and F5 generation did not have any adverse phenotypic effect on milk quality.

  6. High-fidelity real-time maritime scene rendering

    Science.gov (United States)

    Shyu, Hawjye; Taczak, Thomas M.; Cox, Kevin; Gover, Robert; Maraviglia, Carlos; Cahill, Colin

    2011-06-01

    The ability to simulate authentic engagements using real-world hardware is an increasingly important tool. For rendering maritime environments, scene generators must be capable of rendering radiometrically accurate scenes with correct temporal and spatial characteristics. When the simulation is used as input to real-world hardware or human observers, the scene generator must operate in real-time. This paper introduces a novel, real-time scene generation capability for rendering radiometrically accurate scenes of backgrounds and targets in maritime environments. The new model is an optimized and parallelized version of the US Navy CRUISE_Missiles rendering engine. It was designed to accept environmental descriptions and engagement geometry data from external sources, render a scene, transform the radiometric scene using the electro-optical response functions of a sensor under test, and output the resulting signal to real-world hardware. This paper reviews components of the scene rendering algorithm, and details the modifications required to run this code in real-time. A description of the simulation architecture and interfaces to external hardware and models is presented. Performance assessments of the frame rate and radiometric accuracy of the new code are summarized. This work was completed in FY10 under Office of Secretary of Defense (OSD) Central Test and Evaluation Investment Program (CTEIP) funding and will undergo a validation process in FY11.

  7. Light Space Cascaded Shadow Maps Algorithm for Real Time Rendering

    Institute of Scientific and Technical Information of China (English)

    Xiao-Hui Liang; Shang Ma; Li-Xia Cen; Zhuo Yu

    2011-01-01

    Owing to its generality and efficiency, Cascaded Shadow Maps (CSMs) has an important role in real-time shadow rendering in large scale and complex virtual environments. However, CSMs suffers from redundant rendering problem --objects are rendered undesirably to different shadow map textures when view direction and light direction are not perpendicular. In this paper, we present a light space cascaded shadow maps algorithm. The algorithm splits a scene into non-intersecting layers in light space, and generates one shadow map for each layer through irregular frustum clipping and scene organization, ensuring that any shadow sample point never appears in multiple shadow maps. A succinct shadow determination method is given to choose the optimal shadow map when rendering scenes. We also combine the algorithm with stable cascaded shadow maps and soft shadow algorithm to avoid shadow flicking and produce soft shadows. The results show that the algorithm effectively improves the efficiency and shadow quality of CSMs by avoiding redundant rendering, and can produce high-quality shadow rendering in large scale dynamic environments with real-time performance.

  8. Desorption of biocides from renders modified with acrylate and silicone.

    Science.gov (United States)

    Styszko, Katarzyna; Bollmann, Ulla E; Wangler, Timothy P; Bester, Kai

    2014-01-01

    Biocides are used in the building industry to prevent algal, bacterial and fungal growth on polymericrenders and thus to protect buildings. However, these biocides are leached into the environment. To better understand this leaching, the sorption/desorption of biocides in polymeric renders was assessed. In this study the desorption constants of cybutryn, carbendazim, iodocarb, isoproturon, diuron, dichloro-N-octylisothiazolinone and tebuconazole towards acrylate and silicone based renders were assessed at different pH values. At pH 9.5 (porewater) the constants for an acrylate based render varied between 8 (isoproturon) and 9634 (iodocarb) and 3750 (dichloro-N-octylisothiazolinone), respectively. The values changed drastically with pH value. The results for the silicone based renders were in a similar range and usually the compounds with high sorption constants for one polymer also had high values for the other polymer. Comparison of the octanol water partitioning constants (Kow) with the render/water partitioning constants (Kd) revealed similarities, but no strong correlation. Adding higher amounts of polymer to the render material changed the equilibria for dichloro-N-octylisothiazolinone, tebuconazole, cybutryn, carbendazim but not for isoproturon and diuron. PMID:24059976

  9. Parallel Rendering of Large Time-Varying Volume Data

    Science.gov (United States)

    Garbutt, Alexander E.

    2005-01-01

    Interactive visualization of large time-varying 3D volume datasets has been and still is a great challenge to the modem computational world. It stretches the limits of the memory capacity, the disk space, the network bandwidth and the CPU speed of a conventional computer. In this SURF project, we propose to develop a parallel volume rendering program on SGI's Prism, a cluster computer equipped with state-of-the-art graphic hardware. The proposed program combines both parallel computing and hardware rendering in order to achieve an interactive rendering rate. We use 3D texture mapping and a hardware shader to implement 3D volume rendering on each workstation. We use SGI's VisServer to enable remote rendering using Prism's graphic hardware. And last, we will integrate this new program with ParVox, a parallel distributed visualization system developed at JPL. At the end of the project, we Will demonstrate remote interactive visualization using this new hardware volume renderer on JPL's Prism System using a time-varying dataset from selected JPL applications.

  10. Transgenics, agroindustry and food sovereignty

    Directory of Open Access Journals (Sweden)

    Xavier Alejandro León Vega

    2014-10-01

    Full Text Available Food sovereignty has been implemented constitutionally in Ecuador; however, many of the actions and policies are designed to benefit the dominant model of food production, based in agroindustry, intensive monocultures, agrochemicals and transgenics. This article reflects upon the role of family farming as a generator of food sovereignty, and secondly the threat to them by agroindustry agriculture based in transgenic. The role played by food aid in the introduction of transgenic in Latin America and other regions of the world is also analyzed.

  11. Overexpression of a MADS-box gene from birch (Betula platyphylla promotes flowering and enhances chloroplast development in transgenic tobacco.

    Directory of Open Access Journals (Sweden)

    Guan-Zheng Qu

    Full Text Available In this study, a MADS-box gene (BpMADS, which is an ortholog of AP1 from Arabidopsis, was isolated from birch (Betula platyphylla. Transgenic Arabidopsis containing a BpMADS promoter::GUS construct was produced, which exhibited strong GUS staining in sepal tissues. Ectopic expression of BpMADS significantly enhanced the flowering of tobacco (35S::BpMADS. In addition, the chloroplasts of transgenic tobacco exhibited much higher growth and division rates, as well rates of photosynthesis, than wild-type. A grafting experiment demonstrated that the flowering time of the scion was not affected by stock that overexpressed BpMADS. In addition, the overexpression of BpMADS resulted in the upregulation of some flowering-related genes in tobacco.

  12. The Arabidopsis apyrase AtAPY1 is localized in the Golgi instead of the extracellular space

    OpenAIRE

    Schiller Madlen; Massalski Carolin; Kurth Thomas; Steinebrunner Iris

    2012-01-01

    Abstract Background The two highly similar Arabidopsis apyrases AtAPY1 and AtAPY2 were previously shown to be involved in plant growth and development, evidently by regulating extracellular ATP signals. The subcellular localization of AtAPY1 was investigated to corroborate an extracellular function. Results Transgenic Arabidopsis lines expressing AtAPY1 fused to the SNAP-(O6-alkylguanine-DNA alkyltransferase)-tag were used for indirect immunofluorescence and AtAPY1 was detected in punctate st...

  13. Degradation of β-Aryl Ether Bonds in Transgenic Plants

    DEFF Research Database (Denmark)

    Mnich, Ewelina

    cell wall. The aim of the study was to alter lignin structure by expression in plants of the enzymes from S. paucimobilis involved in ether bond degradation (LigDFG). Arabidopsis thaliana and Brachypodium distachyon transgenic lines were generated and characterized with respect to lignin structure and......Lignin is one of the main building blocks of the plant cell wall. It tethers the cell wall by cross-linking with polysaccharides conferring mechanical strength to plants, aiding water transport and providing a mechanical barrier against pathogens. It is generated by the polymerization of the....... Compared to other plants grass cell walls contain elevated amount of ferulates which play a crucial role in cross-linking of polysaccharides and lignin. In addition ferulates are believed to be nucleation cites for the lignification. The bacterium Sphingomonas paucimobilis SYK6 has developed an enzyme...

  14. Production of Transgenic Tall Fescue Plants with Enhanced Stress Tolerances by Agrobacterium tumefaciens-Mediated Transformation

    Institute of Scientific and Technical Information of China (English)

    WU Guan-ting; CHEN Jin-qing; HU Zhang-hua; LANG Chun-xiu; CHEN Xiao-yun; WANG Fu-lin; JIN Wei; XIA Ying-wu

    2006-01-01

    In order to improve stress tolerances of turf-type tall fescue (Festuca arundinacea Schreb.), Agrobacterium tumefaciens strain EHA105 carrying plasmid pCMD containing stress tolerance-related CBF1 gene from Arabidopsis thaliana was used to transform mature seeds-derived embryogenic calli of four cultivars. A total of 112 transgenic plants were regenerated from 32 independent lines and verified by histochemical detection of GUS activity, PCR assay and Southern hybridization analysis. The transformation frequency ranged from 0.92 to 2.87% with apparent differences among the cultivars. Stress tolerances of transgenic plants were enhanced, which was shown by the facts that transgenic plants had distinct growth superiority and significantly higher survival rate than non-transformed ones under high salinity and high osmosis stresses,and that relative electronic conductivity of in vitro leaves treated with low and high temperatures, dehydration and high salinity stresses was 25-30% lower in transgenic plants than in control plants. In addition, it was observed that growth of transgenic plants was inhibited due to constitutive overexpression of CBF1 gene under normal environmental conditions.

  15. Effects of transgenic soybean on growth and phosphorus acquisition in mixed culture system

    Institute of Scientific and Technical Information of China (English)

    Jianna Xie; Jia Zhou; Xiurong Wang; Hong Liao

    2015-01-01

    Transgenic soybean plants overexpressing the Arabidopsis purple acid phosphatase gene AtPAP15 (OXp) or the soybean expansin gene GmEXPB2 (OXe) can improve phosphorous (P) efficiency in pure culture by increasing Apase secretion or changing root morphology. In this study, soybean‐soybean mixed cultures were employed to il uminate P acquisition among plants in mixed stands of transgenic and wild‐type soybean. Our results showed that transgenic soybean plants were much more competitive, and had greater growth and P uptake than wild‐type soybean in mixed culture in both low P calcareous and acid soils. Furthermore, OXe plants had an advantage in calcareous soils when mixed with OXp, whereas the latter performed much better in acid soils. In soybean‐maize mixed culture, transgenic soybean had no impact on maize growth compared to controls in both acid and calcareous soils with different P conditions. As for soybean in mixed culture, OXp plants had no significant advantages regardless of P availability or soil type, while P efficiency improved in OXe in calcareous soils compared to controls. These results imply that physiological traits could be easily affected by the mixed maize. Transgenic soybean plants with enhanced root traits had more competitive advantages than those with improved root physiology in mixed culture.

  16. Transgene teknikker erstatter problematisk avl

    DEFF Research Database (Denmark)

    Alstrup, Aage Kristian Olsen; Hansen, Axel Kornerup

    2016-01-01

    Dyremodeller har ofte været baseret på avl, der ud fra et alment velfærdsmæssigt synspunkt var problematisk. Transgene teknikker kan ofte forbedre dyrevelfærden ved at erstatte disse traditionelle avlsmetoder.......Dyremodeller har ofte været baseret på avl, der ud fra et alment velfærdsmæssigt synspunkt var problematisk. Transgene teknikker kan ofte forbedre dyrevelfærden ved at erstatte disse traditionelle avlsmetoder....

  17. Functional analysis of the theobroma cacao NPR1 gene in arabidopsis

    Directory of Open Access Journals (Sweden)

    Verica Joseph

    2010-11-01

    Full Text Available Abstract Background The Arabidopsis thaliana NPR1 gene encodes a transcription coactivator (NPR1 that plays a major role in the mechanisms regulating plant defense response. After pathogen infection and in response to salicylic acid (SA accumulation, NPR1 translocates from the cytoplasm into the nucleus where it interacts with other transcription factors resulting in increased expression of over 2000 plant defense genes contributing to a pathogen resistance response. Results A putative Theobroma cacao NPR1 cDNA was isolated by RT-PCR using degenerate primers based on homologous sequences from Brassica, Arabidopsis and Carica papaya. The cDNA was used to isolate a genomic clone from Theobroma cacao containing a putative TcNPR1 gene. DNA sequencing revealed the presence of a 4.5 kb coding region containing three introns and encoding a polypeptide of 591 amino acids. The predicted TcNPR1 protein shares 55% identity and 78% similarity to Arabidopsis NPR1, and contains each of the highly conserved functional domains indicative of this class of transcription factors (BTB/POZ and ankyrin repeat protein-protein interaction domains and a nuclear localization sequence (NLS. To functionally define the TcNPR1 gene, we transferred TcNPR1 into an Arabidopsis npr1 mutant that is highly susceptible to infection by the plant pathogen Pseudomonas syringae pv. tomato DC3000. Driven by the constitutive CaMV35S promoter, the cacao TcNPR1 gene partially complemented the npr1 mutation in transgenic Arabidopsis plants, resulting in 100 fold less bacterial growth in a leaf infection assay. Upon induction with SA, TcNPR1 was shown to translocate into the nucleus of leaf and root cells in a manner identical to Arabidopsis NPR1. Cacao NPR1 was also capable of participating in SA-JA signaling crosstalk, as evidenced by the suppression of JA responsive gene expression in TcNPR1 overexpressing transgenic plants. Conclusion Our data indicate that the TcNPR1 is a functional

  18. Heterologous expression in transgenic mosquitoes

    Institute of Scientific and Technical Information of China (English)

    Santhosh P K; Yu hua Deng; Weidong Gu; Xiaoguang Chen

    2010-01-01

    Arthropod-borne diseases such as malaria and dengue virus afflict billions of people worldwide imposing major economic and social burdens. Control of such pathogens is mainly performed by vector management and treatment of affected individuals with drugs. The failure of these conventional approaches due to emergence of insecticide-resistant insects and drug-resistant parasites demonstrate the need of novel and efficacious control strategies to combat these diseases. Genetic modification(GM) of mosquito vectors to impair their ability to be infected and transmit pathogens has emerged as a new strategy to reduce transmission of many vector-borne diseases and deliver public health gains. Several advances in developing transgenic mosquitoes unable to transmit pathogens have gained support, some of them attempt to manipulate the naturally occurring endogenous refractory mechanisms, while others initiate the identification of an exogenous foreign gene which disrupt the pathogen development in insect vectors. Heterologous expression of transgenes under a native or heterologous promoter is important for the screening and effecting of the transgenic mosquitoes. The effect of the transgene on mosquito fitness is a crucial parameter influencing the success of this transgenic approach. This review examines these two aspects and describes the basic research work that has been accomplished towards understanding the complex relation between the parasite and its vector and focuses on recent advances and perspectives towards construction of transgenic mosquitoes refractory to vector-borne disease transmission.

  19. Biodegradation of atrazine in transgenic plants expressing a modified bacterial atrazine chlorohydrolase (atzA) gene.

    Science.gov (United States)

    Wang, Lin; Samac, Deborah A; Shapir, Nir; Wackett, Lawrence P; Vance, Carroll P; Olszewski, Neil E; Sadowsky, Michael J

    2005-09-01

    Atrazine is one of the most widely used herbicides in the USA. Atrazine chlorohydrolase (AtzA), the first enzyme in a six-step pathway leading to the mineralization of atrazine in Gram-negative soil bacteria, catalyses the hydrolytic dechlorination and detoxification of atrazine to hydroxyatrazine. In this study, we investigated the potential use of transgenic plants expressing atzA to take up, dechlorinate and detoxify atrazine. Alfalfa, Arabidopsis thaliana and tobacco were transformed with a modified bacterial atzA gene, p-atzA, under the control of the cassava vein mosaic virus promoter. All transgenic plant species actively expressed p-atzA and grew over a wide range of atrazine concentrations. Thin layer chromatography analyses indicated that in planta expression of p-atzA resulted in the production of hydroxyatrazine. Hydroponically grown transgenic tobacco and alfalfa dechlorinated atrazine to hydroxyatrazine in leaves, stems and roots. Moreover, p-atzA was found to be useful as a conditional-positive selection system to isolate alfalfa and Arabidopsis transformants following Agrobacterium-mediated transformation. Our work suggests that the in planta expression of p-atzA may be useful for the development of plants for the phytoremediation of atrazine-contaminated soils and soil water, and as a marker gene to select for the integration of exogenous DNA into the plant genome. PMID:17173634

  20. Rapid expression of transgenes driven by seed-specific constructs in leaf tissue: DHA production

    Directory of Open Access Journals (Sweden)

    Zhou Xue-Rong

    2010-03-01

    Full Text Available Abstract Background Metabolic engineering of seed biosynthetic pathways to diversify and improve crop product quality is a highly active research area. The validation of genes driven by seed-specific promoters is time-consuming since the transformed plants must be grown to maturity before the gene function can be analysed. Results In this study we demonstrate that genes driven by seed-specific promoters contained within complex constructs can be transiently-expressed in the Nicotiana benthamiana leaf-assay system by co-infiltrating the Arabidopsis thaliana LEAFY COTYLEDON2 (LEC2 gene. A real-world case study is described in which we first assembled an efficient transgenic DHA synthesis pathway using a traditional N. benthamiana Cauliflower Mosaic Virus (CaMV 35S-driven leaf assay before using the LEC2-extended assay to rapidly validate a complex seed-specific construct containing the same genes before stable transformation in Arabidopsis. Conclusions The LEC2-extended N. benthamiana assay allows the transient activation of seed-specific promoters in leaf tissue. In this study we have used the assay as a rapid preliminary screen of a complex seed-specific transgenic construct prior to stable transformation, a feature that will become increasingly useful as genetic engineering moves from the manipulation of single genes to the engineering of complex pathways. We propose that the assay will prove useful for other applications wherein rapid expression of transgenes driven by seed-specific constructs in leaf tissue are sought.

  1. Gravity-regulated gene expression in Arabidopsis thaliana

    Science.gov (United States)

    Sederoff, Heike; Brown, Christopher S.; Heber, Steffen; Kajla, Jyoti D.; Kumar, Sandeep; Lomax, Terri L.; Wheeler, Benjamin; Yalamanchili, Roopa

    Plant growth and development is regulated by changes in environmental signals. Plants sense environmental changes and respond to them by modifying gene expression programs to ad-just cell growth, differentiation, and metabolism. Functional expression of genes comprises many different processes including transcription, translation, post-transcriptional and post-translational modifications, as well as the degradation of RNA and proteins. Recently, it was discovered that small RNAs (sRNA, 18-24 nucleotides long), which are heritable and systemic, are key elements in regulating gene expression in response to biotic and abiotic changes. Sev-eral different classes of sRNAs have been identified that are part of a non-cell autonomous and phloem-mobile network of regulators affecting transcript stability, translational kinetics, and DNA methylation patterns responsible for heritable transcriptional silencing (epigenetics). Our research has focused on gene expression changes in response to gravistimulation of Arabidopsis roots. Using high-throughput technologies including microarrays and 454 sequencing, we iden-tified rapid changes in transcript abundance of genes as well as differential expression of small RNA in Arabidopsis root apices after minutes of reorientation. Some of the differentially regu-lated transcripts are encoded by genes that are important for the bending response. Functional mutants of those genes respond faster to reorientation than the respective wild type plants, indicating that these proteins are repressors of differential cell elongation. We compared the gravity responsive sRNAs to the changes in transcript abundances of their putative targets and identified several potential miRNA: target pairs. Currently, we are using mutant and transgenic Arabidopsis plants to characterize the function of those miRNAs and their putative targets in gravitropic and phototropic responses in Arabidopsis.

  2. Volume rendering in treatment planning for moving targets

    International Nuclear Information System (INIS)

    Advances in computer technologies have facilitated the development of tools for 3-dimensional visualization of CT-data sets with volume rendering. The company Fovia has introduced a high definition volume rendering engine (HDVR trademark by Fovia Inc., Palo Alto, USA) that is capable of representing large CT data sets with high user interactivity even on standard PCs. Fovia provides a software development kit (SDK) that offers control of all the features of the rendering engine. We extended the SDK by functionalities specific to the task of treatment planning for moving tumors. This included navigation of the patient's anatomy in beam's eye view, fast point-and-click measurement of lung tumor trajectories as well as estimation of range perturbations due to motion by calculation of (differential) water equivalent path lengths for protons and carbon ions on 4D-CT data sets. We present patient examples to demonstrate the advantages and disadvantages of volume rendered images as compared to standard 2-dimensional axial plane images. Furthermore, we show an example of a range perturbation analysis. We conclude that volume rendering is a powerful technique for the representation and analysis of large time resolved data sets in treatment planning

  3. Architecture for high performance stereoscopic game rendering on Android

    Science.gov (United States)

    Flack, Julien; Sanderson, Hugh; Shetty, Sampath

    2014-03-01

    Stereoscopic gaming is a popular source of content for consumer 3D display systems. There has been a significant shift in the gaming industry towards casual games for mobile devices running on the Android™ Operating System and driven by ARM™ and other low power processors. Such systems are now being integrated directly into the next generation of 3D TVs potentially removing the requirement for an external games console. Although native stereo support has been integrated into some high profile titles on established platforms like Windows PC and PS3 there is a lack of GPU independent 3D support for the emerging Android platform. We describe a framework for enabling stereoscopic 3D gaming on Android for applications on mobile devices, set top boxes and TVs. A core component of the architecture is a 3D game driver, which is integrated into the Android OpenGL™ ES graphics stack to convert existing 2D graphics applications into stereoscopic 3D in real-time. The architecture includes a method of analyzing 2D games and using rule based Artificial Intelligence (AI) to position separate objects in 3D space. We describe an innovative stereo 3D rendering technique to separate the views in the depth domain and render directly into the display buffer. The advantages of the stereo renderer are demonstrated by characterizing the performance in comparison to more traditional render techniques, including depth based image rendering, both in terms of frame rates and impact on battery consumption.

  4. An Arabidopsis callose synthase

    DEFF Research Database (Denmark)

    Ostergaard, Lars; Petersen, Morten; Mattsson, Ole;

    2002-01-01

    unclear whether callose synthases can also produce cellulose and whether plant cellulose synthases may also produce beta-1,3-glucans. We describe here an Arabidopsis gene, AtGsl5, encoding a plasma membrane-localized protein homologous to yeast beta-1,3-glucan synthase whose expression partially......Beta-1,3-glucan polymers are major structural components of fungal cell walls, while cellulosic beta-1,4-glucan is the predominant polysaccharide in plant cell walls. Plant beta-1,3-glucan, called callose, is produced in pollen and in response to pathogen attack and wounding, but it has been...

  5. Real-Time Rendering of Teeth with No Preprocessing

    DEFF Research Database (Denmark)

    Larsen, Christian Thode; Frisvad, Jeppe Revall; Jensen, Peter Dahl Ejby;

    2012-01-01

    We present a technique for real-time rendering of teeth with no need for computational or artistic preprocessing. Teeth constitute a translucent material consisting of several layers; a highly scattering material (dentine) beneath a semitransparent layer (enamel) with a transparent coating (saliva......). In this study we examine how light interacts with this multilayered structure. In the past, rendering of teeth has mostly been done using image-based texturing or volumetric scans. We work with surface scans and have therefore developed a simple way of estimating layer thicknesses. We use scattering...... properties based on measurements reported in the optics literature, and we compare rendered results qualitatively to images of ceramic teeth created by denturists....

  6. Algorithms for Haptic Rendering of 3D Objects

    Science.gov (United States)

    Basdogan, Cagatay; Ho, Chih-Hao; Srinavasan, Mandayam

    2003-01-01

    Algorithms have been developed to provide haptic rendering of three-dimensional (3D) objects in virtual (that is, computationally simulated) environments. The goal of haptic rendering is to generate tactual displays of the shapes, hardnesses, surface textures, and frictional properties of 3D objects in real time. Haptic rendering is a major element of the emerging field of computer haptics, which invites comparison with computer graphics. We have already seen various applications of computer haptics in the areas of medicine (surgical simulation, telemedicine, haptic user interfaces for blind people, and rehabilitation of patients with neurological disorders), entertainment (3D painting, character animation, morphing, and sculpting), mechanical design (path planning and assembly sequencing), and scientific visualization (geophysical data analysis and molecular manipulation).

  7. Distributed GPU Volume Rendering of ASKAP Spectral Data Cubes

    CERN Document Server

    Hassan, A H; Barnes, D G

    2010-01-01

    The Australian SKA Pathfinder (ASKAP) will be producing 2.2 terabyte HI spectral-line cubes for each 8 hours of observation by 2013. Global views of spectral data cubes are vital for the detection of instrumentation errors, the identification of data artefacts and noise characteristics, and the discovery of strange phenomena, unexpected relations, or unknown patterns. We have previously presented the first framework that can render ASKAP-sized cubes at interactive frame rates. The framework provides the user with a real-time interactive volume rendering by combining shared and distributed memory architectures, distributed CPUs and graphics processing units (GPUs), using the ray-casting algorithm. In this paper we present two main extensions of this framework which are: using a multi-panel display system to provide a high resolution rendering output, and the ability to integrate automated data analysis tools into the visualization output and to interact with its output in place.

  8. Clustered deep shadow maps for integrated polyhedral and volume rendering

    KAUST Repository

    Bornik, Alexander

    2012-01-01

    This paper presents a hardware-accelerated approach for shadow computation in scenes containing both complex volumetric objects and polyhedral models. Our system is the first hardware accelerated complete implementation of deep shadow maps, which unifies the computation of volumetric and geometric shadows. Up to now such unified computation was limited to software-only rendering . Previous hardware accelerated techniques can handle only geometric or only volumetric scenes - both resulting in the loss of important properties of the original concept. Our approach supports interactive rendering of polyhedrally bounded volumetric objects on the GPU based on ray casting. The ray casting can be conveniently used for both the shadow map computation and the rendering. We show how anti-aliased high-quality shadows are feasible in scenes composed of multiple overlapping translucent objects, and how sparse scenes can be handled efficiently using clustered deep shadow maps. © 2012 Springer-Verlag.

  9. Remote visualization system based on particle based volume rendering

    Science.gov (United States)

    Kawamura, Takuma; Idomura, Yasuhiro; Miyamura, Hiroko; Takemiya, Hiroshi; Sakamoto, Naohisa; Koyamada, Koji

    2015-01-01

    In this paper, we propose a novel remote visualization system based on particle-based volume rendering (PBVR),1 which enables interactive analyses of extreme scale volume data located on remote computing systems. The re- mote PBVR system consists of Server, which generates particles for rendering, and Client, which processes volume rendering, and the particle data size becomes significantly smaller than the original volume data. Depending on network bandwidth, the level of detail of images is flexibly controlled to attain high frame rates. Server is highly parallelized on various parallel platforms with hybrid programing model. The mapping process is accelerated by two orders of magnitudes compared with a single CPU. The structured and unstructured volume data with ~108 cells is processed within a few seconds. Compared with commodity Client/Server visualization tools, the total processing cost is dramatically reduced by using proposed system.

  10. Bioavailability of nanoparticulate hematite to Arabidopsis thaliana.

    Science.gov (United States)

    Marusenko, Yevgeniy; Shipp, Jessie; Hamilton, George A; Morgan, Jennifer L L; Keebaugh, Michael; Hill, Hansina; Dutta, Arnab; Zhuo, Xiaoding; Upadhyay, Nabin; Hutchings, James; Herckes, Pierre; Anbar, Ariel D; Shock, Everett; Hartnett, Hilairy E

    2013-03-01

    The environmental effects and bioavailability of nanoparticulate iron (Fe) to plants are currently unknown. Here, plant bioavailability of synthesized hematite Fe nanoparticles was evaluated using Arabidopsis thaliana (A. thaliana) as a model. Over 56-days of growing wild-type A. thaliana, the nanoparticle-Fe and no-Fe treatments had lower plant biomass, lower chlorophyll concentrations, and lower internal Fe concentrations than the Fe-treatment. Results for the no-Fe and nanoparticle-Fe treatments were consistently similar throughout the experiment. These results suggest that nanoparticles (mean diameter 40.9 nm, range 22.3-67.0 nm) were not taken up and therefore not bioavailable to A. thaliana. Over 14-days growing wild-type and transgenic (Type I/II proton pump overexpression) A. thaliana, the Type I plant grew more than the wild-type in the nanoparticle-Fe treatment, suggesting Type I plants cope better with Fe limitation; however, the nanoparticle-Fe and no-Fe treatments had similar growth for all plant types. PMID:23262070

  11. Emotion rendering in auditory simulations of imagined walking styles

    DEFF Research Database (Denmark)

    Turchet, Luca; Rodá, Antonio

    2016-01-01

    This paper investigated how different emotional states of a walker can be rendered and recognized by means of footstep sounds synthesis algorithms. In a first experiment, participants were asked to render, according to imagined walking scenarios, five emotions (aggressive, happy, neutral, sad, and...... tender) by manipulating the parameters of synthetic footstep sounds simulating various combinations of surface materials and shoes types. Results allowed to identify, for the involved emotions and sound conditions, the mean values and ranges of variation of two parameters, sound level and temporal...

  12. Chromium Renderserver: Scalable and Open Source Remote RenderingInfrastructure

    Energy Technology Data Exchange (ETDEWEB)

    Paul, Brian; Ahern, Sean; Bethel, E. Wes; Brugger, Eric; Cook,Rich; Daniel, Jamison; Lewis, Ken; Owen, Jens; Southard, Dale

    2007-12-01

    Chromium Renderserver (CRRS) is software infrastructure thatprovides the ability for one or more users to run and view image outputfrom unmodified, interactive OpenGL and X11 applications on a remote,parallel computational platform equipped with graphics hardwareaccelerators via industry-standard Layer 7 network protocolsand clientviewers. The new contributions of this work include a solution to theproblem of synchronizing X11 and OpenGL command streams, remote deliveryof parallel hardware-accelerated rendering, and a performance analysis ofseveral different optimizations that are generally applicable to avariety of rendering architectures. CRRSis fully operational, Open Sourcesoftware.

  13. Depth of Field Effects for Interactive Direct Volume Rendering

    KAUST Repository

    Schott, Mathias

    2011-06-01

    In this paper, a method for interactive direct volume rendering is proposed for computing depth of field effects, which previously were shown to aid observers in depth and size perception of synthetically generated images. The presented technique extends those benefits to volume rendering visualizations of 3D scalar fields from CT/MRI scanners or numerical simulations. It is based on incremental filtering and as such does not depend on any precomputation, thus allowing interactive explorations of volumetric data sets via on-the-fly editing of the shading model parameters or (multi-dimensional) transfer functions. © 2011 The Author(s).

  14. Photorepair mutants of Arabidopsis

    International Nuclear Information System (INIS)

    UV radiation induces two major DNA damage products, the cyclobutane pyrimidine dimer (CPD) and, at a lower frequency, the pyrimidine (6-4) pyrimidinone dimer (6-4 product). Although Escherichia coli and Saccharomyces cerevisiae produce a CPD-specific photolyase that eliminates only this class of dimer, Arabidopsis thaliana, Drosophila melanogaster, Crotalus atrox, and Xenopus laevis have recently been shown to photoreactivate both CPDs and 6-4 products. We describe the isolation and characterization of two new classes of mutants of Arabidopsis, termed uvr2 and uvr3, that are defective in the photoreactivation of CPDs and 6-4 products, respectively. We demonstrate that the CPD photolyase mutation is genetically linked to a DNA sequence encoding a type II (metazoan) CPD photolyase. In addition, we are able to generate plants in which only CPDs or 6-4 products are photoreactivated in the nuclear genome by exposing these mutants to UV light and then allowing them to repair one or the other class of dimers. This provides us with a unique opportunity to study the biological consequences of each of these two major UV-induced photoproducts in an intact living system

  15. A Sweetpotato Geranylgeranyl Pyrophosphate Synthase Gene, IbGGPS, Increases Carotenoid Content and Enhances Osmotic Stress Tolerance in Arabidopsis thaliana.

    Directory of Open Access Journals (Sweden)

    Wei Chen

    Full Text Available Sweetpotato highly produces carotenoids in storage roots. In this study, a cDNA encoding geranylgeranyl phyrophosphate synthase (GGPS, named IbGGPS, was isolated from sweetpotato storage roots. Green fluorescent protein (GFP was fused to the C-terminus of IbGGPS to obtain an IbGGPS-GFP fusion protein that was transiently expressed in both epidermal cells of onion and leaves of tobacco. Confocal microscopic analysis determined that the IbGGPS-GFP protein was localized to specific areas of the plasma membrane of onion and chloroplasts in tobacco leaves. The coding region of IbGGPS was cloned into a binary vector under the control of 35S promoter and then transformed into Arabidopsis thaliana to obtain transgenic plants. High performance liquid chromatography (HPLC analysis showed a significant increase of total carotenoids in transgenic plants. The seeds of transgenic and wild-type plants were germinated on an agar medium supplemented with polyethylene glycol (PEG. Transgenic seedlings grew significantly longer roots than wild-type ones did. Further enzymatic analysis showed an increased activity of superoxide dismutase (SOD in transgenic seedlings. In addition, the level of malondialdehyde (MDA was reduced in transgenics. qRT-PCR analysis showed altered expressions of several genes involved in the carotenoid biosynthesis in transgenic plants. These data results indicate that IbGGPS is involved in the biosynthesis of carotenoids in sweetpotato storage roots and likely associated with tolerance to osmotic stress.

  16. Lactoferrin-derived resistance against plant pathogens in transgenic plants.

    Science.gov (United States)

    Lakshman, Dilip K; Natarajan, Savithiry; Mandal, Sudhamoy; Mitra, Amitava

    2013-12-01

    Lactoferrin (LF) is a ubiquitous cationic iron-binding milk glycoprotein that contributes to nutrition and exerts a broad-spectrum primary defense against bacteria, fungi, protozoa, and viruses in mammals. These qualities make lactoferrin protein and its antimicrobial motifs highly desirable candidates to be incorporated in plants to impart broad-based resistance against plant pathogens or to economically produce them in bulk quantities for pharmaceutical and nutritional purposes. This study introduced bovine LF (BLF) gene into tobacco ( Nicotiana tabacum var. Xanthi), Arabidopsis ( A. thaliana ) and wheat ( Triticum aestivum ) via Agrobacterium -mediated plant transformation. Transgenic plants or detached leaves exhibited high levels of resistance against the damping-off causing fungal pathogen Rhizoctonia solani and the head blight causing fungal pathogen Fusarium graminearum . LF also imparted resistance to tomato plants against a bacterial pathogen, Ralstonia solanacearum . Similarly, other researchers demonstrated expression of LF and LF-mediated high-quality resistance to several other aggressive fungal and bacterial plant pathogens in transgenic plants and against viral pathogens by foliar applications of LF or its derivatives. Taken together, these studies demonstrated the effectiveness of LF for improving crop quality and its biopharming potentials for pharmaceautical and nutritional applications. PMID:23889215

  17. Transformation of Arabidopsis thaliana via Agrobacterium tumefacience with an endochitinase gene from Trichoderma, and enhanced resistance to Sclerotinia sclerotiorum

    Institute of Scientific and Technical Information of China (English)

    DAI Fu-ming; XU Tong

    2004-01-01

    @@ Sclerotinia sclerotiorum is an important pathogen to many crops and is especially damaging to rape in China. As a model plant Arabidopsis thaliana (ColO) was transformed by spraying Agrobacterium tumefacience with Trichoderma endochitinase gene ThEn-42 at initial bud stage. Eleven seedlings (corresponding to about 0.22 percent transformation) exhibited resistance to hygromycin. The DNA fragment unique to endochitinase ( ThEn-42 ) was amplified by Arabidopsis leaf-PCR or genomic DNA PCR. Unfertile, dwarf and normal phenotypes appeared in the T1 generation. In addition, an enhanced resistance to S. sclerotiorum was observed. The mortality percentage (7.7% to 33.3%) in transgenic plants was significantly lower than in non-transgenic plants (86. 7%) 10 days after inoculation with the pathogen.

  18. Arabidopsis CPR5 Independently Regulates Seed Germination and Postgermination Arrest of Development through LOX Pathway and ABA Signaling

    OpenAIRE

    Guilan Gao; Shengchun Zhang; Chengfeng Wang; Xiang Yang; Yaqin Wang; Xiaojun Su; Jinju Du; Chengwei Yang

    2011-01-01

    The phytohormone abscisic acid (ABA) and the lipoxygenases (LOXs) pathway play important roles in seed germination and seedling growth and development. Here, we reported on the functional characterization of Arabidopsis CPR5 in the ABA signaling and LOX pathways. The cpr5 mutant was hypersensitive to ABA in the seed germination, cotyledon greening and root growth, whereas transgenic plants overexpressing CPR5 were insensitive. Genetic analysis demonstrated that CPR5 gene may be located downst...

  19. Plant hemoglobin gene expression adjusts Arabidopsis susceptibility to Pseudomonas synringae and Botrytis cinerea though scavenging of nitric oxide

    DEFF Research Database (Denmark)

    Sivakumaran, Anushen; Hebelstrup, Kim; Cristescu, Simona;

    2011-01-01

    NO has earlier been shown to influence ethylene production during Pseudomonas syringae elicited hypersensitive response in tobacco. In this work Arabidopsis plants with silencing or null mutation of hemoglobin genes (glb1 and glb2) and transgenic lines over-expressing Glb1 and Glb2 demonstrated a...... causal link between NO generation, hemoglobin-dependent NO scavenging, the production of ethylene and resistance to Botrytis or Pseudomonas....

  20. Defects in leaf epidermis of Arabidopsis thaliana plants with CDKA;1 activity reduced in the shoot apical meristem

    OpenAIRE

    Borowska-Wykret, Dorota; Elsner, Joanna; De Veylder, Lieven; Kwiatkowska, Dorota

    2012-01-01

    In Arabidopsis thaliana, like in other dicots, the shoot epidermis originates from protodermis, the outermost cell layer of shoot apical meristem. We examined leaf epidermis in transgenic A. thaliana plants in which CDKA;1.N146, a negative dominant allele of A-type cyclin-dependent kinase, was expressed from the SHOOTMERISTEMLESS promoter, i.e., in the shoot apical meristem. Using cleared whole mount preparations of expanding leaves and sequential in vivo replicas of expanding leaf surface, w...

  1. Arabidopsis VQ motif-containing proteins VQ12 and VQ29 negatively modulate basal defense against Botrytis cinerea

    OpenAIRE

    Houping Wang; Yanru Hu; Jinjing Pan; Diqiu Yu

    2015-01-01

    Arabidopsis VQ motif-containing proteins have recently been demonstrated to interact with several WRKY transcription factors; however, their specific biological functions and the molecular mechanisms underlying their involvement in defense responses remain largely unclear. Here, we showed that two VQ genes, VQ12 and VQ29, were highly responsive to the necrotrophic fungal pathogen Botrytis cinerea. To characterize their roles in plant defense, we generated amiR-vq12 transgenic plants by using ...

  2. 17 CFR 256.457 - Services rendered to associate companies.

    Science.gov (United States)

    2010-04-01

    ... companies. 256.457 Section 256.457 Commodity and Securities Exchanges SECURITIES AND EXCHANGE COMMISSION (CONTINUED) UNIFORM SYSTEM OF ACCOUNTS FOR MUTUAL SERVICE COMPANIES AND SUBSIDIARY SERVICE COMPANIES, PUBLIC UTILITY HOLDING COMPANY ACT OF 1935 Income and Expense Accounts § 256.457 Services rendered to...

  3. Matching rendered and real world images by digital image processing

    Science.gov (United States)

    Mitjà, Carles; Bover, Toni; Bigas, Miquel; Escofet, Jaume

    2010-05-01

    Recent advances in computer-generated images (CGI) have been used in commercial and industrial photography providing a broad scope in product advertising. Mixing real world images with those rendered from virtual space software shows a more or less visible mismatching between corresponding image quality performance. Rendered images are produced by software which quality performance is only limited by the resolution output. Real world images are taken with cameras with some amount of image degradation factors as lens residual aberrations, diffraction, sensor low pass anti aliasing filters, color pattern demosaicing, etc. The effect of all those image quality degradation factors can be characterized by the system Point Spread Function (PSF). Because the image is the convolution of the object by the system PSF, its characterization shows the amount of image degradation added to any taken picture. This work explores the use of image processing to degrade the rendered images following the parameters indicated by the real system PSF, attempting to match both virtual and real world image qualities. The system MTF is determined by the slanted edge method both in laboratory conditions and in the real picture environment in order to compare the influence of the working conditions on the device performance; an approximation to the system PSF is derived from the two measurements. The rendered images are filtered through a Gaussian filter obtained from the taking system PSF. Results with and without filtering are shown and compared measuring the contrast achieved in different final image regions.

  4. An experiment on the color rendering of different light sources

    Science.gov (United States)

    Fumagalli, Simonetta; Bonanomi, Cristian; Rizzi, Alessandro

    2013-02-01

    The color rendering index (CRI) of a light source attempts to measure how much the color appearance of objects is preserved when they are illuminated by the given light source. This problem is of great importance for various industrial and scientific fields, such as lighting architecture, design, ergonomics, etc. Usually a light source is specified through the Correlated Color Temperature or CCT. However two (or more) light sources with the same CCT but different spectral power distribution can exist. Therefore color samples viewed under two light sources with equal CCTs can appear different. Hence, the need for a method to assess the quality of a given illuminant in relation to color. Recently CRI has had a renewed interest because of the new LED-based lighting systems. They usually have a color rendering index rather low, but good preservation of color appearance and a pleasant visual appearance (visual appeal). Various attempts to develop a new color rendering index have been done so far, but still research is working for a better one. This article describes an experiment performed by human observers concerning the appearance preservation of color under some light sources, comparing it with a range of available color rendering indices.

  5. Remote parallel rendering for high-resolution tiled display walls

    KAUST Repository

    Nachbaur, Daniel

    2014-11-01

    © 2014 IEEE. We present a complete, robust and simple to use hardware and software stack delivering remote parallel rendering of complex geometrical and volumetric models to high resolution tiled display walls in a production environment. We describe the setup and configuration, present preliminary benchmarks showing interactive framerates, and describe our contributions for a seamless integration of all the software components.

  6. Democratizing rendering for multiple viewers in surround VR systems

    KAUST Repository

    Schulze, Jürgen P.

    2012-03-01

    We present a new approach for how multiple users\\' views can be rendered in a surround virtual environment without using special multi-view hardware. It is based on the idea that different parts of the screen are often viewed by different users, so that they can be rendered from their own view point, or at least from a point closer to their view point than traditionally expected. The vast majority of 3D virtual reality systems are designed for one head-tracked user, and a number of passive viewers. Only the head tracked user gets to see the correct view of the scene, everybody else sees a distorted image. We reduce this problem by algorithmically democratizing the rendering view point among all tracked users. Researchers have proposed solutions for multiple tracked users, but most of them require major changes to the display hardware of the VR system, such as additional projectors or custom VR glasses. Our approach does not require additional hardware, except the ability to track each participating user. We propose three versions of our multi-viewer algorithm. Each of them balances image distortion and frame rate in different ways, making them more or less suitable for certain application scenarios. Our most sophisticated algorithm renders each pixel from its own, optimized camera perspective, which depends on all tracked users\\' head positions and orientations. © 2012 IEEE.

  7. Color-rendering indices in global illumination methods

    Science.gov (United States)

    Geisler-Moroder, David; Dür, Arne

    2009-10-01

    Human perception of material colors depends heavily on the nature of the light sources that are used for illumination. One and the same object can cause highly different color impressions when lit by a vapor lamp or by daylight, respectively. On the basis of state-of-the-art colorimetric methods, we present a modern approach for the calculation of color-rendering indices (CRI), which were defined by the International Commission on Illumination (CIE) to characterize color reproduction properties of illuminants. We update the standard CIE method in three main points: first, we use the CIELAB color space; second, we apply a linearized Bradford transformation for chromatic adaptation; and finally, we evaluate color differences using the CIEDE2000 total color difference formula. Moreover, within a real-world scene, light incident on a measurement surface is composed of a direct and an indirect part. Neumann and Schanda [Proc. CGIV'06 Conf., Leeds, UK, pp. 283-286 (2006)] have shown for the cube model that diffuse interreflections can influence the CRI of a light source. We analyze how color-rendering indices vary in a real-world scene with mixed direct and indirect illumination and recommend the usage of a spectral rendering engine instead of an RGB-based renderer for reasons of accuracy of CRI calculations.

  8. Diffusion tensor visualization using random field correlation and volume rendering

    OpenAIRE

    Sigfridsson, Andreas; Estepar, R.; Wigström, Lars; Alberola, C; Westin, C-F

    2003-01-01

    The visualization of diffusion tensor fields remains a challenging topic. A representation based on volume rendering of a scalar field is presented. The method uses the tensor to correlate a noise field in the direction of greater diffusivity while preserving the high frequency components of the noise field in transversal diffusion directions.

  9. Interacting with Stroke-Based Rendering on a Wall Display

    NARCIS (Netherlands)

    Grubert, Jens; Hanckock, Mark; Carpendale, Sheelagh; Tse, Edward; Isenberg, Tobias

    2007-01-01

    We introduce two new interaction techniques for creating and interacting with non-photorealistic images using stroke-based rendering. We provide bimanual control of a large interactive canvas through both remote pointing and direct touch. Remote pointing allows people to sit and interact at a distan

  10. Transgenic agriculture and environmental indicators

    Directory of Open Access Journals (Sweden)

    Denize Dias de Carvalho

    2006-12-01

    Full Text Available Despite the rapid diffusion of transgenic crops, there are still few environmental impact studies capable of supplying a conclusive scientific response in regard to its technical and economic advantages and disadvantages. Prospective scenarios were elaborated to assist environmental impact assessment, using techniques derived from SWOT (Strength, Weakness, Opportunity, Threat analysis and the DPSIR (Driving Force – human activity, Pressure, State, Impact, Response model, to evaluate the environmental indicators and the relationship between them. Control and management actions were identified, searching the integration of aspects related to the biotechnology applied to transgenic processes, biodiversity, biosafety and intellectual property. It was demonstrated that the DPSIR model is, in fact, an instrument for integrated environmental assessment and the application of the proposed methodology resulted in favorable indicators to the adoption of transgenic agriculture. The elaborated scenarios are useful to develop an Environmental Management System (EMS to agriculture.

  11. [Transgenic animals and animal welfare

    Science.gov (United States)

    Reinhardt, Christoph

    1998-01-01

    Under the pressure of a public vote in Switzerland (7 June 1998) on an initiative to ban the production, use and patenting of transgenic animals, their value for biomedical research and development is intensely debated. In addition, the Swiss legislation has adopted (1992) a constitutional obligation to "take into account the dignity of creatures". The term "dignity of creatures", however, can be interpreted in anthropocentric or biocentric ways. The government has now formulated the legal implications of this term for transgenic animals and plants in various laws including the animal and environmental protection laws. This paper gives arguments for a fair evaluation of trangenic animals from an animal welfare point of view where not only the costs of animal suffering must be considered but also the probability of potential benefit for man. A self-confident research community should allow such an evaluation procedure even in view of an outcome which could ban many uses of transgenic animals PMID:11208266

  12. Transgenic woody plants for biofuel

    Institute of Scientific and Technical Information of China (English)

    Wei Tang; Anna Y.Tang

    2014-01-01

    Transgenic trees as a new source for biofuel have brought a great interest in tree biotechnology. Genetically modifying forest trees for ethanol production have advantages in technical challenges, costs, environmental concerns, and financial problems over some of crops. Genetic engineering of forest trees can be used to reduce the level of lignin, to produce the fast-growing trees, to develop trees with higher cellulose, and to allow the trees to be grown more widely. Trees can establish themselves in the field with less care of farmers, compared to most of crops. Transgenic crops as a new source for biofuel have been recently reviewed in several reviews. Here, we overview transgenic woody plants as a new source for biofuel including genetically modified woody plants and environment; main focus of woody plants genetic modifications;solar to chemical energy transfer; cellulose biosynthesis;lignin biosynthesis;and cellulosic ethanol as biofuel.

  13. The wheat MAP kinase phosphatase 1 alleviates salt stress and increases antioxidant activities in Arabidopsis.

    Science.gov (United States)

    Zaidi, Ikram; Ebel, Chantal; Belgaroui, Nibras; Ghorbel, Mouna; Amara, Imène; Hanin, Moez

    2016-04-01

    Mitogen-activated protein kinase phosphatases (MKPs) are important negative regulators in the MAPK signaling pathways, which play crucial roles in plant growth, development and stress responses. We have previously shown that the heterologous expression of a durum wheat MKP, TMKP1, results in increased tolerance to salt stress in yeast but its particular contribution in salt stress tolerance in plants was not investigated. Here, TMKP1 was overexpressed in Arabidopsis thaliana and physiological changes were assessed in transgenic plants exposed to stress conditions. Under salt stress and especially LiCl, the TMKP1 overexpressors displayed higher germination rates in comparison to wild type plants. The enhancement of salt stress tolerance was accompanied by increased antioxidant enzyme activities, namely superoxide dismutase, catalase and peroxydases. Such increases in antioxidant activities were concomitant with lower malondialdehyde, superoxide anion O2(-) and hydrogen peroxide levels in the TMKP1 transgenic seedlings. Moreover, we provide evidence that, in contrast to the Arabidopsis ortholog AtMKP1, TMKP1 acts as a positive regulator of salt stress tolerance via its ectopic expression in the Arabidopsis mkp1 mutant. PMID:26927025

  14. Ectopic expression of a hyacinth AGL6 homolog caused earlier flowering and homeotic conversion in Arabidopsis

    Institute of Scientific and Technical Information of China (English)

    2007-01-01

    MADS-box genes are involved in floral organ development. Here we report that an AGL6(Agamous-like 6)-like MADS-box gene, HoAGL6, was isolated from Hyacinthus orientalis L. Expression pattern analysis demonstrated that HoAGL6 transcript was detected in inflorescence buds, tepals, carpels and ovules, but not in stamina, leaves or scales. Transgenic Arabidopsis plants ectopically expressing HoAGL6 exhibited novel phenotypes of significantly reduced plant size, extremely early flowering, and losing inflorescence indeterminacy. In addition, wide homeotic conversion of sepals, petals, and leaves into carpel-like or ovary structures, and disappearance or number reduction of stamens in 35S::HoAGL6 Arabidopsis plants were also observed. RT-PCR analysis indicated that the expressions of flowering time gene SOC1 and flower meristem identity gene LFY were significantly up-regulated in 35S::HoAGL6 transgenic Arabidopsis plants, and the expression levels of floral organ identity genes AG and SEP1 in leaves were also elevated. These results indicated that HoAGL6 was involved in the regulation of flower transition and flower organ formation.

  15. Human anti-rhesus D IgG1 antibody produced in transgenic plants

    DEFF Research Database (Denmark)

    Bouquin, Thomas; Thomsen, Mads; Nielsen, Leif Kofoed; Green, Trine Hefsgaard; Mundy, John; Dziegiel, Morten Hanefeld

    2002-01-01

    Transgenic plants represent an alternative to cell culture systems for producing cheap and safe antibodies for diagnostic and therapeutic use. To evaluate the functional properties of a 'plantibody', we generated transgenic Arabidopsis plants expressing full-length human IgG1 against the Rhesus D...... antigen, which is responsible for alloimmunization of RhD- mothers carrying an RhD+ fetus. Anti-RhD extracted from plants specifically reacted with RhD+ cells in antiglobulin technique, and elicited a respiratory burst in human peripheral blood mononuclear cells. Plant-derived antibody had equivalent...... properties to CHO cell-produced anti-RhD antibody, indicating its potential usefulness in diagnostic and therapeutic programs....

  16. Human anti-rhesus D IgG1 antibody produced in transgenic plants

    DEFF Research Database (Denmark)

    Bouquin, Thomas; Thomsen, Mads Jonas Birkbak; Nielsen, Leif Kofoed;

    2002-01-01

    antigen, which is responsible for alloimmunization of RhD- mothers carrying an RhD+ fetus. Anti-RhD extracted from plants specifically reacted with RhD+ cells in antiglobulin technique, and elicited a respiratory burst in human peripheral blood mononuclear cells. Plant-derived antibody had equivalent......Transgenic plants represent an alternative to cell culture systems for producing cheap and safe antibodies for diagnostic and therapeutic use. To evaluate the functional properties of a 'plantibody', we generated transgenic Arabidopsis plants expressing full-length human IgG1 against the Rhesus D...... properties to CHO cell-produced anti-RhD antibody, indicating its potential usefulness in diagnostic and therapeutic programs....

  17. Development of Marker-Free Transgenic Potato Tubers Enriched in Caffeoylquinic Acids and Flavonols.

    Science.gov (United States)

    Li, Yang; Tang, Wenzhao; Chen, Jing; Jia, Ru; Ma, Lianjie; Wang, Shaoli; Wang, Jiao; Shen, Xiangling; Chu, Zhaohui; Zhu, Changxiang; Ding, Xinhua

    2016-04-13

    Potato (Solanum tuberosum L.) is a major crop worldwide that meets human economic and nutritional requirements. Potato has several advantages over other crops: easy to cultivate and store, cheap to consume, and rich in a variety of secondary metabolites. In this study, we generated three marker-free transgenic potato lines that expressed the Arabidopsis thaliana flavonol-specific transcriptional activator AtMYB12 driven by the tuber-specific promoter Patatin. Marker-free potato tubers displayed increased amounts of caffeoylquinic acids (CQAs) (3.35-fold increases on average) and flavonols (4.50-fold increase on average). Concentrations of these metabolites were associated with the enhanced expression of genes in the CQA and flavonol biosynthesis pathways. Accumulation of CQAs and flavonols resulted in 2-fold higher antioxidant capacity compared to wild-type potatoes. Tubers from these marker-free transgenic potatoes have therefore improved antioxidant properties. PMID:27019017

  18. Transgenic mouse offspring generated by ROSI

    OpenAIRE

    Moreira, Pedro; Pérez-Cerezales, Serafín; LAGUNA, Ricardo; FERNÁNDEZ-GONZALEZ, Raúl; SANJUANBENITO, Belén Pintado; Gutiérrez-Adán, Alfonso

    2015-01-01

    The production of transgenic animals is an important tool for experimental and applied biology. Over the years, many approaches for the production of transgenic animals have been tried, including pronuclear microinjection, sperm-mediated gene transfer, transfection of male germ cells, somatic cell nuclear transfer and the use of lentiviral vectors. In the present study, we developed a new transgene delivery approach, and we report for the first time the production of transgenic animals by co-...

  19. Ectopic expression of a Catalpa bungei (Bignoniaceae) PISTILLATA homologue rescues the petal and stamen identities in Arabidopsis pi-1 mutant.

    Science.gov (United States)

    Jing, Danlong; Xia, Yan; Chen, Faju; Wang, Zhi; Zhang, Shougong; Wang, Junhui

    2015-02-01

    PISTILLATA (PI) plays crucial roles in Arabidopsis flower development by specifying petal and stamen identities. To investigate the molecular mechanisms underlying organ development of woody angiosperm in Catalpa, we isolated and identified a PI homologue, referred to as CabuPI (C. bungei PISTILLATA), from two genetically cognate C. bungei (Bignoniaceae) bearing single and double flowers. Sequence and phylogenetic analyses revealed that the gene is closest related to the eudicot PI homologues. Moreover, a highly conserved PI-motif is found in the C-terminal regions of CabuPI. Semi-quantitative and quantitative real time PCR analyses showed that the expression of CabuPI was restricted to petals and stamens. However, CabuPI expression in the petals and stamens persisted throughout all floral development stages, but the expression levels were different. In 35S::CabuPI transgenic homozygous pi-1 mutant Arabidopsis, the second and the third whorl floral organs produced normal petals and a different number of stamens, respectively. Furthermore, ectopic expression of the CabuPI in transgenic wild-type or heterozygote pi-1 mutant Arabidopsis caused the first whorl sepal partially converted into a petal-like structure. These results clearly reveal the functional conservation of PI homologues between C. bungei and Arabidopsis. PMID:25575990

  20. Inducible and constitutive expression of an elicitor gene Hrip1 from Alternaria tenuissima enhances stress tolerance in Arabidopsis.

    Science.gov (United States)

    Peng, Xue-Cong; Qiu, De-Wen; Zeng, Hong-Mei; Guo, Li-Hua; Yang, Xiu-Fen; Liu, Zheng

    2015-02-01

    Hrip1 is a novel hypersensitive response-inducing protein secreted by Alternaria tenuissima that activates defense responses and systemic acquired resistance in tobacco. This study investigates the role that Hrip1 plays in responses to abiotic and biotic stress using transgenic Arabidopsis thaliana expressing the Hrip1 gene under the control of the stress-inducible rd29A promoter or constitutive cauliflower mosaic virus 35S promoter. Bioassays showed that inducible Hrip1 expression in rd29A∷Hrip1 transgenic lines had a significantly higher effect on plant height, silique length, plant dry weight, seed germination and root length under salt and drought stress compared to expression in 35S∷Hrip1 lines and wild type plants. The level of enhancement of resistance to Botrytis cinerea by the 35S∷Hrip1 lines was higher than in the rd29A∷Hrip1 lines. Moreover, stress-related gene expression in the transgenic Arabidopsis lines was significantly increased by 200 mM NaCl and 200 mM mannitol treatments, and defense genes in the jasmonic acid and ethylene signaling pathway were significantly up-regulated after Botrytis inoculation in the Hrip1 transgenic plants. Furthermore, the activity of some antioxidant enzymes, such as peroxidase and catalase increased after salt and drought stress and Botrytis infection. These results suggested that the Hrip1 protein contributes to abiotic and biotic resistance in transgenic Arabidopsis and may be used as a useful gene for resistance breeding in crops. Although the constitutive expression of Hrip1 is suitable for biotic resistance, inducible Hrip1 expression is more responsive for abiotic resistance. PMID:25120219

  1. Arabidopsis SOI33/AtENT8 Gene Encodes a Putative Equilibrative Nucleoside Transporter That Is Involved in Cytokinin Transport In Planta

    Institute of Scientific and Technical Information of China (English)

    Jiaqiang SUN; Naoya HIROSE; Xingchun WANG; Pei WEN; Li XUE; Hitoshi SAKAKIBARA; Jianru ZUO

    2005-01-01

    The plant phytohormone cytokinin plays an important role in many facets of plant growth and development by regulating cell division and differentiation. Recent studies have shed significant light into the mechanisms of cytokinin metabolism and signaling. However, little is known about how the hormone is transported in planta, although it has been proposed that the hormone is presumably transported in nucleoside-conjugated forms. Here, we report the identification and characterization of cytokinin transport ers in Arabidopsis. We previously reported that a gain-of-function mutation in the PGA22/AtIPT8 gene caused overproduction of cytokinins in planta. In an effort to screen for suppressor of pga22/atipt8 (soi) mutants, we identified a mutant soi33-1. Molecular and genetic analyses indicated that SOI33 encodes a putative equilibrative nucleoside transporter (ENT), previously designated as AtENT8. Members of this small gene family are presumed to be involved in the transport of nucleosides in eukaryotic cells. Under conditions of nitrogen starvation, loss-of-function mutations in SOI33/AtENT8 or in a related gene AtENT3 cause a reduced sensitivity to the nucleoside-type cytokinins isopentenyladenine riboside (iPR) and trans zeatin riboside (tZR), but display a normal response to the free base-type cytokinins isopentenyladenine (iP) and trans-zeatin (tZ). Conversely, overexpression of SOI33/AtENT8 renders transgenic plants hyper sensitive to iPR but not to iP. An in planta measurement experiment indicated that uptake efficiency of 3H labeled iPR was reduced more than 40% in soi33 and atent3 mutants. However, a mutation inAtENT1 had no substantial effect on the cytokinin response and iPR uptake efficiency. Our results suggest that SOI33/ AtENT8 and AtENT3 are involved in the transport of nucleoside-type cytokinins in Arabidopsis.

  2. Overexpression of AtAP1M3 regulates flowering time and floral development in Arabidopsis and effects key flowering-related genes in poplar.

    Science.gov (United States)

    Chen, Zhong; Ye, Meixia; Su, Xiaoxing; Liao, Weihua; Ma, Huandi; Gao, Kai; Lei, Bingqi; An, Xinmin

    2015-08-01

    APETALA1 plays a crucial role in the transition from vegetative to reproductive phase and in floral development. In this study, to determine the effect of AP1 expression on flowering time and floral organ development, transgenic Arabidopsis and poplar overexpressing of AtAP1M3 (Arabidopsis AP1 mutant by dominant negative mutation) were generated. Transgenic Arabidopsis with e35Spro::AtAP1M3 displayed phenotypes with delayed-flowering compared to wild-type and flowers with abnormal sepals, petals and stamens. In addition, transgenic Arabidopsis plants exhibited reduced growth vigor compared to the wild-type plants. Ectopic expression of AtAP1M3 in poplar resulted in up- or down-regulation of some endogenous key flowering-related genes, including floral meristems identity gene LFY, B-class floral organ identity genes AP3 and PI, flowering pathway integrator FT1 and flower repressors TFL1 and SVP. These results suggest that AtAP1M3 regulates flowering time and floral development in plants. PMID:25820621

  3. A model-free method for annotating on vascular structure in volume rendered images

    Science.gov (United States)

    He, Wei; Li, Yanfang; Shi, Weili; Miao, Yu; He, Fei; Yan, Fei; Yang, Huamin; Zhang, Huimao; Mori, Kensaku; Jiang, Zhengang

    2015-03-01

    The precise annotation of vessel is desired in computer-assisted systems to help surgeons identify each vessel branch. A method has been reported that annotates vessels on volume rendered images by rendering their names on them using a two-pass rendering process. In the reported method, however, cylinder surface models of the vessels should be generated for writing vessels names. In fact, vessels are not actual cylinders, so the surfaces of the vessels cannot be simulated by such models accurately. This paper presents a model-free method for annotating vessels on volume rendered images by rendering their names on them using the two-pass rendering process: surface rendering and volume rendering. In the surface rendering process, docking points of vessel names are estimated by using such properties as centerlines, running directions, and vessel regions which are obtained in preprocess. Then the vessel names are pasted on the vessel surfaces at the docking points. In the volume rendering process, volume image is rendered using a fast volume rendering algorithm with depth buffer of image rendered in the surface rendering process. Finally, those rendered images are blended into an image as a result. In order to confirm the proposed method, a visualizing system for the automated annotation of abdominal arteries is performed. The experimental results show that vessel names can be drawn on the corresponding vessel in the volume rendered images correctly. The proposed method has enormous potential to be adopted to annotate other organs which cannot be modeled using regular geometrical surface.

  4. Expression of Vitis amurensis NAC26 in Arabidopsis enhances drought tolerance by modulating jasmonic acid synthesis.

    Science.gov (United States)

    Fang, Linchuan; Su, Lingye; Sun, Xiaoming; Li, Xinbo; Sun, Mengxiang; Karungo, Sospeter Karanja; Fang, Shuang; Chu, Jinfang; Li, Shaohua; Xin, Haiping

    2016-04-01

    The growth and fruit quality of grapevines are widely affected by abnormal climatic conditions such as water deficits, but many of the precise mechanisms by which grapevines respond to drought stress are still largely unknown. Here, we report that VaNAC26, a member of the NAC transcription factor family, was upregulated dramatically during cold, drought and salinity treatments in Vitis amurensis, a cold and drought-hardy wild Vitis species. Heterologous overexpression of VaNAC26 enhanced drought and salt tolerance in transgenic Arabidopsis. Higher activities of antioxidant enzymes and lower concentrations of H2O2 and O2 (-) were found in VaNAC26-OE lines than in wild type plants under drought stress. These results indicated that scavenging by reactive oxygen species (ROS) was enhanced by VaNAC26 in transgenic lines. Microarray-based transcriptome analysis revealed that genes related to jasmonic acid (JA) synthesis and signaling were upregulated in VaNAC26-OE lines under both normal and drought conditions. VaNAC26 showed a specific binding ability on the NAC recognition sequence (NACRS) motif, which broadly exists in the promoter regions of upregulated genes in transgenic lines. Endogenous JA content significantly increased in the VaNAC26-OE lines 2 and 3. Our data suggest that VaNAC26 responds to abiotic stresses and may enhance drought tolerance by transcriptional regulation of JA synthesis in Arabidopsis. PMID:27162276

  5. Expression of Vitis amurensis NAC26 in Arabidopsis enhances drought tolerance by modulating jasmonic acid synthesis

    Science.gov (United States)

    Fang, Linchuan; Su, Lingye; Sun, Xiaoming; Li, Xinbo; Sun, Mengxiang; Karungo, Sospeter Karanja; Fang, Shuang; Chu, Jinfang; Li, Shaohua; Xin, Haiping

    2016-01-01

    The growth and fruit quality of grapevines are widely affected by abnormal climatic conditions such as water deficits, but many of the precise mechanisms by which grapevines respond to drought stress are still largely unknown. Here, we report that VaNAC26, a member of the NAC transcription factor family, was upregulated dramatically during cold, drought and salinity treatments in Vitis amurensis, a cold and drought-hardy wild Vitis species. Heterologous overexpression of VaNAC26 enhanced drought and salt tolerance in transgenic Arabidopsis. Higher activities of antioxidant enzymes and lower concentrations of H2O2 and O2 − were found in VaNAC26-OE lines than in wild type plants under drought stress. These results indicated that scavenging by reactive oxygen species (ROS) was enhanced by VaNAC26 in transgenic lines. Microarray-based transcriptome analysis revealed that genes related to jasmonic acid (JA) synthesis and signaling were upregulated in VaNAC26-OE lines under both normal and drought conditions. VaNAC26 showed a specific binding ability on the NAC recognition sequence (NACRS) motif, which broadly exists in the promoter regions of upregulated genes in transgenic lines. Endogenous JA content significantly increased in the VaNAC26-OE lines 2 and 3. Our data suggest that VaNAC26 responds to abiotic stresses and may enhance drought tolerance by transcriptional regulation of JA synthesis in Arabidopsis.

  6. Ectopic Expression of the Chinese Cabbage Malate Dehydrogenase Gene Promotes Growth and Aluminum Resistance in Arabidopsis.

    Science.gov (United States)

    Li, Qing-Fei; Zhao, Jing; Zhang, Jing; Dai, Zi-Hui; Zhang, Lu-Gang

    2016-01-01

    Malate dehydrogenases (MDHs) are key metabolic enzymes that play important roles in plant growth and development. In the present study, we isolated the full-length and coding sequences of BraMDH from Chinese cabbage [Brassica campestris L. ssp. pekinensis (Lour) Olsson]. We conducted bioinformatics analysis and a subcellular localization assay, which revealed that the BraMDH gene sequence contained no introns and that BraMDH is localized to the chloroplast. In addition, the expression pattern of BraMDH in Chinese cabbage was investigated, which revealed that BraMDH was heavily expressed in inflorescence apical meristems, as well as the effect of BraMDH overexpression in two homozygous transgenic Arabidopsis lines, which resulted in early bolting and taller inflorescence stems. Furthermore, the fresh and dry weights of aerial tissue from the transgenic Arabidopsis plants were significantly higher than those from the corresponding wild-type plants, as were plant height, the number of rosette leaves, and the number of siliques produced, and the transgenic plants also exhibited stronger aluminum resistance when treated with AlCl3. Therefore, our results suggest that BraMDH has a dramatic effect on plant growth and that the gene is involved in both plant growth and aluminum resistance. PMID:27536317

  7. Transcriptional profiling of pea ABR17 mediated changes in gene expression in Arabidopsis thaliana

    Directory of Open Access Journals (Sweden)

    Deyholos Michael K

    2008-09-01

    Full Text Available Abstract Background Pathogenesis-related proteins belonging to group 10 (PR10 are elevated in response to biotic and abiotic stresses in plants. Previously, we have shown a drastic salinity-induced increase in the levels of ABR17, a member of the PR10 family, in pea. Furthermore, we have also demonstrated that the constitutive expression of pea ABR17 cDNA in Arabidopsis thaliana and Brassica napus enhances their germination and early seedling growth under stress. Although it has been reported that several members of the PR10 family including ABR17 possess RNase activity, the exact mechanism by which the aforementioned characteristics are conferred by ABR17 is unknown at this time. We hypothesized that a study of differences in transcriptome between wild type (WT and ABR17 transgenic A. thaliana may shed light on this process. Results The molecular changes brought about by the expression of pea ABR17 cDNA in A. thaliana in the presence or absence of salt stress were investigated using microarrays consisting of 70-mer oligonucleotide probes representing 23,686 Arabidopsis genes. Statistical analysis identified number of genes which were over represented among up- or down-regulated transcripts in the transgenic line. Our results highlight the important roles of many abscisic acid (ABA and cytokinin (CK responsive genes in ABR17 transgenic lines. Although the transcriptional changes followed a general salt response theme in both WT and transgenic seedlings under salt stress, many genes exhibited differential expression patterns when the transgenic and WT lines were compared. These genes include plant defensins, heat shock proteins, other defense related genes, and several transcriptional factors. Our microarray results for selected genes were validated using quantitative real-time PCR. Conclusion Transcriptional analysis in ABR17 transgenic Arabidopsis plants, both under normal and saline conditions, revealed significant changes in abundance of

  8. Soluble methionine enhances accumulation of a 15 kDa zein, a methionine-rich storage protein, in transgenic alfalfa but not in transgenic tobacco plants.

    Science.gov (United States)

    Amira, Golan; Ifat, Matityahu; Tal, Avraham; Hana, Badani; Shmuel, Galili; Rachel, Amir

    2005-09-01

    With the general aim of elevating the content of the essential amino acid methionine in vegetative tissues of plants, alfalfa (Medicago sativa L.) and tobacco plants, as well as BY2 tobacco suspension cells, were transformed with a beta-zein::3HA gene under the 35S promoter of cauliflower mosaic virus encoding a rumen-stable methionine-rich storage protein of 15 kDa zein. To examine whether soluble methionine content limited the accumulation of the 15 kDa zein::3HA, methionine was first added to the growth medium of the different transgenic plants and the level of the alien protein was determined. Results demonstrated that the added methionine enhanced the accumulation of the 15 kDa zein::3HA in transgenic alfalfa and tobacco BY2 cells, but not in whole transgenic tobacco plants. Next, the endogenous levels of methionine were elevated in the transgenic tobacco and alfalfa plants by crossing them with plants expressing the Arabidopsis cystathionine gamma-synthase (AtCGS) having significantly higher levels of soluble methionine in their leaves. Compared with plants expressing only the 15 kDa zein::3HA, transgenic alfalfa co-expressing both alien genes showed significantly enhanced levels of this protein concurrently with a reduction in the soluble methionine content, thus implying that soluble methionine was incorporated into the 15 kDa zein::3HA. Similar phenomena also occurred in tobacco, but were considerably less pronounced. The results demonstrate that the accumulation of the 15 kDa zein::3HA is regulated in a species-specific manner and that soluble methionine plays a major role in the accumulation of the 15 kDa zein in some plant species but less so in others. PMID:16061510

  9. The MYST histone acetyltransferases are essential for gametophyte development in Arabidopsis

    Directory of Open Access Journals (Sweden)

    Zhou Dao-Xiu

    2008-11-01

    Full Text Available Abstract Background Histone acetyltransferases (HATs play critical roles in the regulation of chromatin structure and gene expression. Arabidopsis genome contains 12 HAT genes, but the biological functions of many of them are still unknown. In this work, we studied the evolutionary relationship and cellular functions of the two Arabidopsis HAT genes homologous to the MYST family members. Results An extensive phylogenetic analysis of 105 MYST proteins revealed that they can be divided into 5 classes, each of which contains a specific combination of protein modules. The two Arabidopsis MYST proteins, HAM1 and HAM2, belong to a "green clade", clearly separated from other families of HATs. Using a reverse genetic approach, we show that HAM1 and HAM2 are a functionally redundant pair of genes, as single Arabidopsis ham1 and ham2 mutants displayed a wild-type phenotype, while no double mutant seedling could be recovered. Genetic analysis and cytological study revealed that ham1ham2 double mutation induced severe defects in the formation of male and female gametophyte, resulting in an arrest of mitotic cell cycle at early stages of gametogenesis. RT-PCR experiments and the analysis of transgenic plants expressing the GUS reporter gene under the HAM1 or the HAM2 promoter showed that both genes displayed an overlapping expression pattern, mainly in growing organs such as shoots and flower buds. Conclusion The work presented here reveals novel properties for MYST HATs in Arabidopsis. In addition to providing an evolutionary relationship of this large protein family, we show the evidence of a link between MYST and gamete formation as previously suggested in mammalian cells. A possible function of the Arabidopsis MYST protein-mediated histone acetylation during cell division is suggested.

  10. Realistic Haptic Rendering of Interacting Deformable Objects in Virtual Environments

    CERN Document Server

    Duriez, Christian; Kheddar, Abderrahmane; Andriot, Claude

    2008-01-01

    A new computer haptics algorithm to be used in general interactive manipulations of deformable virtual objects is presented. In multimodal interactive simulations, haptic feedback computation often comes from contact forces. Subsequently, the fidelity of haptic rendering depends significantly on contact space modeling. Contact and friction laws between deformable models are often simplified in up to date methods. They do not allow a "realistic" rendering of the subtleties of contact space physical phenomena (such as slip and stick effects due to friction or mechanical coupling between contacts). In this paper, we use Signorini's contact law and Coulomb's friction law as a computer haptics basis. Real-time performance is made possible thanks to a linearization of the behavior in the contact space, formulated as the so-called Delassus operator, and iteratively solved by a Gauss-Seidel type algorithm. Dynamic deformation uses corotational global formulation to obtain the Delassus operator in which the mass and s...

  11. Color Rendering Plasmonic Aluminum Substrates with Angular Symmetry Breaking.

    Science.gov (United States)

    Duempelmann, Luc; Casari, Daniele; Luu-Dinh, Angélique; Gallinet, Benjamin; Novotny, Lukas

    2015-12-22

    We fabricate and characterize large-area plasmonic substrates that feature asymmetric periodic nanostructures made of aluminum. Strong coupling between localized and propagating plasmon resonances leads to characteristic Fano line shapes with tunable spectral positions and widths. Distinctive colors spanning the entire visible spectrum are generated by tuning the system parameters, such as the period and the length of the aluminum structures. Moreover, the asymmetry of the aluminum structures gives rise to a strong symmetry broken color rendering effect, for which colors are observed only from one side of the surface normal. Using a combination of immersed laser interference lithography and nanoimprint lithography, our color rendering structures can be fabricated on areas many inches in size. We foresee applications in anticounterfeiting, photovoltaics, sensing, displays, and optical security. PMID:26498131

  12. Rapid exploration of curvilinear grids using direct volume rendering

    Science.gov (United States)

    Vangelder, Allen; Wilhelms, Jane

    1993-01-01

    Fast techniques for direct volume rendering over curvilinear grids of hexahedral cells are developed. This type of 3D grid is common in computational fluid dynamics and finite element analysis. Four new projection methods are presented and compared with each other and with previous methods for tetrahedral grids and rectilinear grids. All four methods use polygon-rendering hardware for speed. A simplified algorithm for visibility ordering, which is based on a combination of breadth-first and depth-first searches, is described. A new multi-pass blending method is described that reduces visual artifacts that are introduced by linear interpolation in hardware where exponential interpolation is needed. Multi-pass blending is of equal interest to hardware-oriented projection methods used on rectilinear grids. Visualization tools that permit rapid data banding and cycling through transfer functions, as well as region restrictions, are described.

  13. The shock response of a rendered porcine fat

    Science.gov (United States)

    Wilgeroth, J. M.; Hazell, P. J.; Appleby-Thomas, G. J.

    2010-11-01

    Characterization of the shock response of biological materials is required in order to develop an understanding of how such materials behave under high strain-rate loading. In this work, a predominately linear Us-up Hugoniot relationship for a rendered porcine fat has been established using the plate-impact technique. This has been shown to take the form Us=1.58+2.47up (ρ0=0.945 g/cc) and comparison has been made between the dynamic behavior of the adipose material and both 20 wt % ballistic gelatin and water. The adipose material has been shown to behave in likeness with simple polymers such as polyethylene and to strengthen under shock loading, unlike ballistic gelatin, which has been shown to behave hydrodynamically. An experimental design incorporating direct insertion of lateral stress gauges within the rendered fat has given insight into both the behavior of lateral gauges and the lateral stress response of the material under dynamic loading.

  14. Characterization of a bifunctional O- and N-glucosyltransferase from Vitis vinifera in glucosylating phenolic compounds and 3,4-dichloroaniline in Pichia pastoris and Arabidopsis thaliana.

    Directory of Open Access Journals (Sweden)

    Zhi-Sheng Xu

    Full Text Available 2,4,5-Trichlorophenol, 2,6-dimethylphenol, 3-methylcatechol, phenol, hydroquinone, catechol, and 3,4-dichloroaniline are present in the environment and are risky to humans and animals because of their wide applications in many industries. In this study, a putative uridine diphosphate glucose-dependent glycosyltransferase from Vitis vinifera (VvUGT72B1 displayed high O-glucosyltransferase or N-glucosyltransferase activity toward all these xenbiotics and was able to enhance the resistance of P. pastoris to them. Compared with wild-type Arabidopsis plants, VvUGT72B1-transgenic Arabidopsis plants showed higher resistance to all the xenobiotics except for phenol and exhibited higher removal efficiencies against all xenobiotics. Glucosides of 3-methylcatechol, 2,6-dimethylphenol, phenol, and 3,4-dichloroaniline were exported to the surrounding media by Arabidopsis plants while transgenic Arabidopsis plants exported more glucosides than wild-type Arabidopsis plants. Our findings have the potential to provide a broader spectrum remediation strategy for the phytoremoval and degradation of phenolic compounds and 3,4-dichloroaniline than previous works.

  15. Biotechnology network promotes knowledge of transgenics

    International Nuclear Information System (INIS)

    Red de Ingenieria Genetica Aplicada al Mejoramiento de Cultivos Tropicales (Rigatrop) integrated by a group of scientists from the Universidad de Costa Rica (UCR), Universidad Nacional (UNA) and of the Instituto Tecnologico de Costa Rica (TEC) have organized two forums on the topic of transgenics. The first forum has shown successful experiences of development of transgenic crops in Latin America, as for example: the transgenic bean, project realized in Brazil and transgenic eggplant in Bangladesh. The second forum has been about transgenics and environment effected at the UCR, on the occasion of World Environment Day. Rigatrop members are working currently in two projects applying biotechnological tools to coffee

  16. Navigating in Virtual Environments with 360o Omnidirectional Rendering

    OpenAIRE

    Ardouin, Jérôme; Lécuyer, Anatole; Marchal, Maud; Marchand, Eric

    2013-01-01

    Typical field-of-view (fov) of visual feedback in virtual reality applications is generally limited. In some cases, e.g. in videogames, the provided fov can be artificially increased, using simple perspective projection methods. In this paper, we design and evaluate different visualization techniques, inspired by the cartography domain, for navigating in virtual environments (VE) with a 360° horizontal fov of the scene. We have conducted an evaluation of different methods compared to a render...

  17. Volume Visual Attention Maps (VVAM) in ray-casting rendering.

    Science.gov (United States)

    Beristain, Andoni; Congote, John; Ruiz, Oscar

    2012-01-01

    This paper presents an extension visual attention maps for volume data visualization, where eye fixation points become rays in the 3D space, and the visual attention map becomes a volume. This Volume Visual Attention Map (VVAM) is used to interactively enhance a ray-casting based direct volume rendering (DVR) visualization. The practical application of this idea into the biomedical image visualization field is explored for interactive visualization. PMID:22356956

  18. Fostering energy efficiency in buildings through aerogel-based renders

    OpenAIRE

    Ibrahim, Mohamad; Wurtz, Etienne; Achard, Patrick; Biwole, Pascal Henry

    2015-01-01

    In France, the building sector is the largest consumer of energy and accounts for about 43% of the total energy consumption and 25% of the CO2 emissions. In this study, we present a recently developed insulating rendering based on silica-aerogels. It is mainly developed for exterior thermal insulation applications. In addition to new buildings, it can be used for retrofitting existing ones since it has a high insulation performance and its application is compatible with the traditional masonr...

  19. Slab-Based Raycasting : Efficient Volume Rendering with CUDA

    OpenAIRE

    Mensmann, Jörg; Ropinski, Timo; Hinrichs, Klaus

    2009-01-01

    GPU-based raycasting is the state-of-the-art rendering technique for interactive volume visualization. The ray traversal is usually implemented in a fragment shader, utilizing the hardware in a way that was not originally intended. New programming interfaces for stream processing, such as CUDA, support a more general programming model and the use of additional device features, which are not accessible through traditional shader programming.We propose a slab-based raycasting technique that is ...

  20. On Rendering Synthetic Images for Training an Object Detector

    OpenAIRE

    Rozantsev, Artem; Lepetit, Vincent; Fua, Pascal

    2014-01-01

    We propose a novel approach to synthesizing images that are effective for training object detectors. Starting from a small set of real images, our algorithm estimates the rendering parameters required to synthesize similar images given a coarse 3D model of the target object. These parameters can then be reused to generate an unlimited number of training images of the object of interest in arbitrary 3D poses, which can then be used to increase classification performances. A key insight of our...

  1. Multiresolution maximum intensity volume rendering by morphological adjunction pyramids

    OpenAIRE

    Roerdink, Jos B. T. M.

    2003-01-01

    We describe a multiresolution extension to maximum intensity projection (MIP) volume rendering, allowing progressive refinement and perfect reconstruction. The method makes use of morphological adjunction pyramids. The pyramidal analysis and synthesis operators are composed of morphological 3-D erosion and dilation, combined with dyadic downsampling for analysis and dyadic upsampling for synthesis. In this case the MIP operator can be interchanged with the synthesis operator. This fact is the...

  2. Comparison of Morphological Pyramids for Multiresolution MIP Volume Rendering

    OpenAIRE

    Roerdink, Jos B. T. M.

    2002-01-01

    We recently proposed a multiresolution representation for maximum intensity projection (MIP) volume rendering based on morphological adjunction pyramids which allow progressive refinement and have the property of perfect reconstruction. In this algorithm the pyramidal analysis and synthesis operators are composed of morphological erosion and dilation, combined with dyadic downsampling for analysis and dyadic upsampling for synthesis. Here we introduce an alternative pyramid scheme in which a ...

  3. Multiresolution Maximum Intensity Volume Rendering by Morphological Pyramids

    OpenAIRE

    Roerdink, Jos B. T. M.; Ebert, D.; Favre, JM; Peikert, R.

    2001-01-01

    We propose a multiresolution representation for maximum intensity projection (MIP) volume rendering, based on morphological pyramids which allow progressive refinement and have the property of perfect reconstruction. The pyramidal analysis and synthesis operators are composed of morphological erosion and dilation, combined with dyadic downsampling for analysis and dyadic upsampling for synthesis. The structure of the multiresolution MIP representation is very similar to wavelet splatting, the...

  4. Capturing, processing, and rendering real-world scenes

    Science.gov (United States)

    Nyland, Lars S.; Lastra, Anselmo A.; McAllister, David K.; Popescu, Voicu; McCue, Chris; Fuchs, Henry

    2000-12-01

    While photographs vividly capture a scene from a single viewpoint, it is our goal to capture a scene in such a way that a viewer can freely move to any viewpoint, just as he or she would in an actual scene. We have built a prototype system to quickly digitize a scene using a laser rangefinder and a high-resolution digital camera that accurately captures a panorama of high-resolution range and color information. With real-world scenes, we have provided data to fuel research in many area, including representation, registration, data fusion, polygonization, rendering, simplification, and reillumination. The real-world scene data can be used for many purposes, including immersive environments, immersive training, re-engineering and engineering verification, renovation, crime-scene and accident capture and reconstruction, archaeology and historic preservation, sports and entertainment, surveillance, remote tourism and remote sales. We will describe our acquisition system, the necessary processing to merge data from the multiple input devices and positions. We will also describe high quality rendering using the data we have collected. Issues about specific rendering accelerators and algorithms will also be presented. We will conclude by describing future uses and methods of collection for real- world scene data.

  5. Informatics in radiology: Render: an online searchable radiology study repository.

    Science.gov (United States)

    Dang, Pragya A; Kalra, Mannudeep K; Schultz, Thomas J; Graham, Steven A; Dreyer, Keith J

    2009-01-01

    Radiology departments are a rich source of information in the form of digital radiology reports and images obtained in patients with a wide spectrum of clinical conditions. A free text radiology report and image search application known as Render was created to allow users to find pertinent cases for a variety of purposes. Render is a radiology report and image repository that pools researchable information derived from multiple systems in near real time with use of (a) Health Level 7 links for radiology information system data, (b) periodic file transfers from the picture archiving and communication system, and (c) the results of natural language processing (NLP) analysis. Users can perform more structured and detailed searches with this application by combining different imaging and patient characteristics such as examination number; patient age, gender, and medical record number; and imaging modality. Use of NLP analysis allows a more effective search for reports with positive findings, resulting in the retrieval of more cases and terms having greater relevance. From the retrieved results, users can save images, bookmark examinations, and navigate to an external search engine such as Google. Render has applications in the fields of radiology education, research, and clinical decision support. PMID:19564253

  6. Efficient Encoding and Rendering of Time-Varying Volume Data

    Science.gov (United States)

    Ma, Kwan-Liu; Smith, Diann; Shih, Ming-Yun; Shen, Han-Wei

    1998-01-01

    Visualization of time-varying volumetric data sets, which may be obtained from numerical simulations or sensing instruments, provides scientists insights into the detailed dynamics of the phenomenon under study. This paper describes a coherent solution based on quantization, coupled with octree and difference encoding for visualizing time-varying volumetric data. Quantization is used to attain voxel-level compression and may have a significant influence on the performance of the subsequent encoding and visualization steps. Octree encoding is used for spatial domain compression, and difference encoding for temporal domain compression. In essence, neighboring voxels may be fused into macro voxels if they have similar values, and subtrees at consecutive time steps may be merged if they are identical. The software rendering process is tailored according to the tree structures and the volume visualization process. With the tree representation, selective rendering may be performed very efficiently. Additionally, the I/O costs are reduced. With these combined savings, a higher level of user interactivity is achieved. We have studied a variety of time-varying volume datasets, performed encoding based on data statistics, and optimized the rendering calculations wherever possible. Preliminary tests on workstations have shown in many cases tremendous reduction by as high as 90% in both storage space and inter-frame delay.

  7. Two Arabidopsis ADP-glucose pyrophosphorylase large subunits (APL1 and APL2) are catalytic.

    Science.gov (United States)

    Ventriglia, Tiziana; Kuhn, Misty L; Ruiz, Ma Teresa; Ribeiro-Pedro, Marina; Valverde, Federico; Ballicora, Miguel A; Preiss, Jack; Romero, José M

    2008-09-01

    ADP-glucose (Glc) pyrophosphorylase (ADP-Glc PPase) catalyzes the first committed step in starch biosynthesis. Higher plant ADP-Glc PPase is a heterotetramer (alpha(2)beta(2)) consisting of two small and two large subunits. There is increasing evidence that suggests that catalytic and regulatory properties of the enzyme from higher plants result from the synergy of both types of subunits. In Arabidopsis (Arabidopsis thaliana), two genes encode small subunits (APS1 and APS2) and four large subunits (APL1-APL4). Here, we show that in Arabidopsis, APL1 and APL2, besides their regulatory role, have catalytic activity. Heterotetramers formed by combinations of a noncatalytic APS1 and the four large subunits showed that APL1 and APL2 exhibited ADP-Glc PPase activity with distinctive sensitivities to the allosteric activator (3-phosphoglycerate). Mutation of the Glc-1-P binding site of Arabidopsis and potato (Solanum tuberosum) isoforms confirmed these observations. To determine the relevance of these activities in planta, a T-DNA mutant of APS1 (aps1) was characterized. aps1 is starchless, lacks ADP-Glc PPase activity, APS1 mRNA, and APS1 protein, and is late flowering in long days. Transgenic lines of the aps1 mutant, expressing an inactivated form of APS1, recovered the wild-type phenotype, indicating that APL1 and APL2 have catalytic activity and may contribute to ADP-Glc synthesis in planta. PMID:18614708

  8. Two Arabidopsis ADP-Glucose Pyrophosphorylase Large Subunits (APL1 and APL2) Are Catalytic1

    Science.gov (United States)

    Ventriglia, Tiziana; Kuhn, Misty L.; Ruiz, Ma Teresa; Ribeiro-Pedro, Marina; Valverde, Federico; Ballicora, Miguel A.; Preiss, Jack; Romero, José M.

    2008-01-01

    ADP-glucose (Glc) pyrophosphorylase (ADP-Glc PPase) catalyzes the first committed step in starch biosynthesis. Higher plant ADP-Glc PPase is a heterotetramer (α2β2) consisting of two small and two large subunits. There is increasing evidence that suggests that catalytic and regulatory properties of the enzyme from higher plants result from the synergy of both types of subunits. In Arabidopsis (Arabidopsis thaliana), two genes encode small subunits (APS1 and APS2) and four large subunits (APL1–APL4). Here, we show that in Arabidopsis, APL1 and APL2, besides their regulatory role, have catalytic activity. Heterotetramers formed by combinations of a noncatalytic APS1 and the four large subunits showed that APL1 and APL2 exhibited ADP-Glc PPase activity with distinctive sensitivities to the allosteric activator (3-phosphoglycerate). Mutation of the Glc-1-P binding site of Arabidopsis and potato (Solanum tuberosum) isoforms confirmed these observations. To determine the relevance of these activities in planta, a T-DNA mutant of APS1 (aps1) was characterized. aps1 is starchless, lacks ADP-Glc PPase activity, APS1 mRNA, and APS1 protein, and is late flowering in long days. Transgenic lines of the aps1 mutant, expressing an inactivated form of APS1, recovered the wild-type phenotype, indicating that APL1 and APL2 have catalytic activity and may contribute to ADP-Glc synthesis in planta. PMID:18614708

  9. Overexpression of Late Embryogenesis Abundant 14 enhances Arabidopsis salt stress tolerance

    Energy Technology Data Exchange (ETDEWEB)

    Jia, Fengjuan, E-mail: jfj.5566@163.com; Qi, Shengdong, E-mail: zisexanwu@163.com; Li, Hui, E-mail: 332453593@qq.com; Liu, Pu, E-mail: banbaokezhan@163.com; Li, Pengcheng, E-mail: lpcsdau@163.com; Wu, Changai, E-mail: cawu@sdau.edu.cn; Zheng, Chengchao, E-mail: cczheng@sdau.edu.cn; Huang, Jinguang, E-mail: jghuang@sdau.edu.cn

    2014-11-28

    Highlights: • It is the first time to investigate the biological function of AtLEA14 in salt stress response. • AtLEA14 enhances the salt stress tolerance both in Arabidopsis and yeast. • AtLEA14 responses to salt stress by stabilizing AtPP2-B11, an E3 ligase, under normal or salt stress conditions. - Abstract: Late embryogenesis abundant (LEA) proteins are implicated in various abiotic stresses in higher plants. In this study, we identified a LEA protein from Arabidopsis thaliana, AtLEA14, which was ubiquitously expressed in different tissues and remarkably induced with increased duration of salt treatment. Subcellular distribution analysis demonstrated that AtLEA14 was mainly localized in the cytoplasm. Transgenic Arabidopsis and yeast overexpressing AtLEA14 all exhibited enhanced tolerance to high salinity. The transcripts of salt stress-responsive marker genes (COR15a, KIN1, RD29B and ERD10) were overactivated in AtLEA14 overexpressing lines compared with those in wild type plants under normal or salt stress conditions. In vivo and in vitro analysis showed that AtLEA14 could effectively stabilize AtPP2-B11, an important E3 ligase. These results suggested that AtLEA14 had important protective functions under salt stress conditions in Arabidopsis.

  10. Interactions between co-expressed Arabidopsis sucrose transporters in the split-ubiquitin system

    Directory of Open Access Journals (Sweden)

    Lalonde Sylvie

    2003-03-01

    Full Text Available Abstract Background The Arabidopsis genome contains nine sucrose transporter paralogs falling into three clades: SUT1-like, SUT2 and SUT4. The carriers differ in their kinetic properties. Many transport proteins are known to exist as oligomers. The yeast-based split ubiquitin system can be used to analyze the ability of membrane proteins to interact. Results Promoter-GUS fusions were used to analyze the cellular expression of the three transporter genes in transgenic Arabidopsis plants. All three fusion genes are co-expressed in companion cells. Protein-protein interactions between Arabidopsis sucrose transporters were tested using the split ubiquitin system. Three paralogous sucrose transporters are capable of interacting as either homo- or heteromers. The interactions are specific, since a potassium channel and a glucose transporter did not show interaction with sucrose transporters. Also the biosynthetic and metabolizing enzymes, sucrose phosphate phosphatase and sucrose synthase, which were found to be at least in part bound to the plasma membrane, did not specifically interact with sucrose transporters. Conclusions The split-ubiquitin system provides a powerful tool to detect potential interactions between plant membrane proteins by heterologous expression in yeast, and can be used to screen for interactions with membrane proteins as baits. Like other membrane proteins, the Arabidopsis sucrose transporters are able to form oligomers. The biochemical approaches are required to confirm the in planta interaction.

  11. Philosophical Reflection on Risks of Transgenic Technology

    Institute of Scientific and Technical Information of China (English)

    Xiaolu WANG

    2012-01-01

    Abstract [Objective] The aim was to analyze risks of transgenic technology. [Method] Discussions on risks of transgenic technologies were conducted from per- spective of philosophy. [Result] Mechanistic philosophy and reductionism are causes of reflection on risks of transgenic technology. Considering transgene is an artificial choice taking place of natural choice, it is inevitable for risks of transgenic technolo- gy to be found, in addition, social system constitutes the root for out-of-control of transgenic technology, hence, mechanism risk is the primary cause of transgenic risks. [Conclusion] It is inescapable for science view to be changed from arbitrary and lopsided to reflective and comprehensive and for technology view to be changed from exterminative and genesic to protective and symbiotic.

  12. The Arabidopsis NIMIN proteins affect NPR1 differentially

    Directory of Open Access Journals (Sweden)

    Meike eHermann

    2013-04-01

    Full Text Available NON-EXPRESSOR OF PATHOGENESIS-RELATED GENES1 (NPR1 is the central regulator of the pathogen defense reaction systemic acquired resistance (SAR. NPR1 acts by sensing the SAR signal molecule salicylic acid (SA to induce expression of PATHOGENESIS-RELATED (PR genes. Mechanistically, NPR1 is the core of a transcription complex interacting with TGA transcription factors and NIM1 INTERACTING (NIMIN proteins. Arabidopsis NIMIN1 has been shown to suppress NPR1 activity in transgenic plants. The Arabidopsis NIMIN family comprises four structurally related, yet distinct members. Here, we show that NIMIN1, NIMIN2 and NIMIN3 are expressed differentially, and that the encoded proteins affect expression of the SAR marker PR-1 differentially. NIMIN3 is expressed constitutively at a low level, but NIMIN2 and NIMIN1 are both responsive to SA. While NIMIN2 is an immediate early SA-induced and NPR1-independent gene, NIMIN1 is activated after NIMIN2, but clearly before PR-1. Notably, NIMIN1, like PR-1, depends on NPR1. In a transient assay system, NIMIN3 suppresses SA-induced PR-1 expression, albeit to a lesser extent than NIMIN1, whereas NIMIN2 does not negatively affect PR-1 gene activation. Furthermore, although binding to the same domain in the C-terminus, NIMIN1 and NIMIN2 interact differentially with NPR1, thus providing a molecular basis for their opposing effects on NPR1. Together, our data suggest that the Arabidopsis NIMIN proteins are regulators of the SAR response. We propose that NIMINs act in a strictly consecutive and SA-regulated manner on the SA sensor protein NPR1, enabling NPR1 to monitor progressing threat by pathogens and to promote appropriate defense gene activation at distinct stages of SAR. In this scenario, the defense gene PR-1 is repressed at the onset of SAR by SA-induced, yet instable NIMIN1.

  13. Enhanced transformation of TNT by Arabidopsis plants expressing an old yellow enzyme.

    Directory of Open Access Journals (Sweden)

    Bo Zhu

    Full Text Available 2,4,6-Trinitrotoluene (TNT is released in nature from manufacturing or demilitarization facilities, as well as after the firing or detonation of munitions or leakage from explosive remnants of war. Environmental contamination by TNT is associated with human health risks, necessitating the development of cost-effective remediation techniques. The lack of affordable and effective cleanup technologies for explosives contamination requires the development of better processes. In this study, we present a system for TNT phytoremediation by overexpressing the old yellow enzyme (OYE3 gene from Saccharomyces cerevisiae. The resulting transgenic Arabidopsis plants demonstrated significantly enhanced TNT tolerances and a strikingly higher capacity to remove TNT from their media. The current work indicates that S. cerevisiae OYE3 overexpression in Arabidopsis is an efficient method for the phytoremoval and degradation of TNT. Our findings have the potential to provide a suitable remediation strategy for sites contaminated by TNT.

  14. Auxin distribution and transport during embryogenesis and seed germi-nation of Arabidopsis

    Institute of Scientific and Technical Information of China (English)

    2001-01-01

    Auxin distribution during embryogenesis and seed germination were studied with transgenic Arabidopsis plants expressing GUS gene driven by a synthetic DR5 promoter, an auxin responsive promoter. The results showed that GUS activity is higher in ends of hypophysis and cotyledon primordia of heart-, torpedo- and cotyledon-stage embryos, leaf tip area, lateral root primordia, root apex and cotyledon of young seedlings.And GUS accumulated in root apex of the seedlings grown on auxin transport inhibitor containing media.All these suggested that above-mentioned part of the organs and tissues have a higher level of auxin, and auxin polar transport inhibitor could cause the accumulation of auxin in root apex. And auxin transport inhibitor also resulted in aberration of Arabidopsis leaf pattern formation, root gravitropism and elongation.

  15. Calcium dynamics in root cells of Arabidopsis thaliana visualized with selective plane illumination microscopy.

    Directory of Open Access Journals (Sweden)

    Alex Costa

    Full Text Available Selective Plane Illumination Microscopy (SPIM is an imaging technique particularly suited for long term in-vivo analysis of transparent specimens, able to visualize small organs or entire organisms, at cellular and eventually even subcellular resolution. Here we report the application of SPIM in Calcium imaging based on Förster Resonance Energy Transfer (FRET. Transgenic Arabidopsis plants expressing the genetically encoded-FRET-based Ca(2+ probe Cameleon, in the cytosol or nucleus, were used to demonstrate that SPIM enables ratiometric fluorescence imaging at high spatial and temporal resolution, both at tissue and single cell level. The SPIM-FRET technique enabled us to follow nuclear and cytosolic Ca(2+ dynamics in Arabidopsis root tip cells, deep inside the organ, in response to different stimuli. A relevant physiological phenomenon, namely Ca(2+ signal percolation, predicted in previous studies, has been directly visualized.

  16. EMF1, a novel protein involved in the control of shoot architecture and flowering in Arabidopsis

    DEFF Research Database (Denmark)

    Aubert, D.; Chen, L.; Moon, Y.-H.;

    2001-01-01

    EMF1 shares common motifs that include nuclear localization signals, P-loop, and LXXLL elements. Alteration of EMF1 expression in transgenic plants caused progressive changes in flowering time, shoot determinacy, and inflorescence architecture. EMF1 and its related sequence may belong to a new class......Shoot architecture and flowering time in angiosperms depend on the balanced expression of a large number of flowering time and flower meristem identity genes. Loss-of-function mutations in the Arabidopsis EMBRYONIC FLOWER (EMF) genes cause Arabidopsis to eliminate rosette shoot growth and transform...... the apical meristem from indeterminate to determinate growth by producing a single terminal flower on all nodes. We have identified the EMF1 gene by positional cloning. The deduced polypeptide has no homology with any protein of known function except a putative protein in the rice genome with which...

  17. Constitutive expression of OsIAA9 affects starch granules accumulation and root gravitropic response in Arabidopsis

    Directory of Open Access Journals (Sweden)

    Sha eLuo

    2015-12-01

    Full Text Available Auxin/Indole-3-Acetic Acid (Aux/IAA genes are early auxin response genes ecoding short-lived transcriptional repressors, which regulate auxin signaling in plants by interplay with Auxin Response Factors (ARFs. Most of the Aux/IAA proteins contain four different domains, namely Domain I, Domain II, Domain III and Domain IV. So far all Aux/IAA mutants with auxin-related phenotypes identified in both Arabidopsis and rice (Oryza sativa are dominant gain-of-function mutants with mutations in Domain II of the corresponding Aux/IAA proteins, suggest that Aux/IAA proteins in both Arabidopsis and rice are largely functional redundantly, and they may have conserved functions. We report here the functional characterization of a rice Aux/IAA gene, OsIAA9. RT-PCR results showed that expression of OsIAA9 was induced by exogenously applied auxin, suggesting that OsIAA9 is an auxin response gene. Bioinformatic analysis showed that OsIAA9 has a repressor motif in Domain I, a degron in Domain II, and the conserved amino acid signatures for protein-protein interactions in Domain III and Domain IV. By generating transgenic plants expressing GFP-OsIAA9 and examining florescence in the transgenic plants, we found that OsIAA9 is localized in the nucleus. When transfected into protoplasts isolated from rosette leaves of Arabidopsis, OsIAA9 repressed reporter gene expression, and the repression was partially released by exogenously IAA. These results suggest that OsIAA9 is a canonical Aux/IAA protein. Protoplast transfection assays showed that OsIAA9 interacted ARF5, but not ARF6, 7, 8 and 19. Transgenic Arabidopsis plants expressing OsIAA9 have increased number of lateral roots, and reduced gravitropic response. Further analysis showed that OsIAA9 transgenic Arabidopsis plants accumulated fewer granules in their root tips and the distribution of granules was also affected. Taken together, our study showed that OsIAA9 is a transcriptional repressor, and it regulates

  18. Focal glomerulosclerosis in proviral and c-fms transgenic mice links Vpr expression to HIV-associated nephropathy

    International Nuclear Information System (INIS)

    Clinical and morphologic features of human immunodeficiency virus (HIV)-associated nephropathy (HIVAN), such as proteinuria, sclerosing glomerulopathy, tubular degeneration, and interstitial disease, have been modeled in mice bearing an HIV proviral transgene rendered noninfectious through a deletion in gag/pol. Exploring the genetic basis of HIVAN, HIV transgenic mice bearing mutations in either or both of the accessory genes nef and vpr were created. Proteinuria and focal glomerulosclerosis (FGS) only developed in mice with an intact vpr gene. Transgenic mice bearing a simplified proviral DNA (encoding only Tat and Vpr) developed renal disease characterized by FGS in which Vpr protein was localized to glomerular and tubular epithelia by immunohistochemistry. The dual transgenic progeny of HIV[Tat/Vpr] mice bred to HIV[ΔVpr] proviral transgenic mice displayed a more severe nephropathy with no apparent increase in Vpr expression, implying that multiple viral genes contribute to HIVAN. However, the unique contribution of macrophage-specific Vpr expression in the development of glomerular disease was underscored by the induction of FGS in multiple murine lines bearing a c-fms/vpr transgene

  19. Hydrogen Sulfide Regulates Ethylene-induced Stomatal Closure in Arabidopsis thaliana

    Institute of Scientific and Technical Information of China (English)

    Zhihui Hou; Lanxiang Wang; Jing Liu; Lixia Hou; Xin Liu

    2013-01-01

    Hydrogen sulfide (H2S) is a newly-discovered signaling molecule in plants and has caused increasing attention in recent years,but its function in stomatal movement is unclear.In plants,H2S is synthesized via cysteine degradation catalyzed by D-/L-cysteine desulfhydrase (D-/L-CDes).AtD-/L-CDes::GUS transgenic Arabidopsis thaliana (L.) Heynh.plants were generated and used to investigate gene expression patterns,and results showed that AtD-/L-CDes can be expressed in guard cells.We also determined the subcellular localization of AtD-/L-CDes using transgenic plants of AtD-/L-CDes::GFP,and the results showed that AtD-CDes and AtL-CDes are located in the chloroplast and in the cytoplasm,respectively.The transcript levels of AtD-CDes and AtL-CDes were affected by the chemicals that cause stomatal closure.Among these factors,ACC,a precursor of ethylene,has the most significant effect,which indicates that the H2S generated from D-/L-CDes may play an important role in ethylene-induced stomatal closure.Meanwhile,H2S synthetic inhibitors significantly inhibited ethylene-induced stomatal closure in Arabidopsis.Ethylene treatment caused an increase of H2S production and of AtD-/L-CDes activity in Arabidopsis leaves.AtD-/L-CDes over-expressing plants exhibited enhanced induction of stomatal closure compared to the wild-type after ethylene treatment; however,the effect was not observed in the Atd-cdes and Atl-cdes mutants.In conclusion,our results suggest that the D-/L-CDes-generated H2S is involved in the regulation of ethylene-induced stomatal closure in Arabidopsis thaliana.

  20. A thermostable β-glucuronidase obtained by directed evolution as a reporter gene in transgenic plants.

    Directory of Open Access Journals (Sweden)

    Ai-Sheng Xiong

    Full Text Available A β-glucuronidase variant, GUS-TR3337, that was obtained by directed evolution exhibited higher thermostability than the wild-type enzyme, GUS-WT. In this study, the utility of GUS-TR337 as an improved reporter was evaluated. The corresponding gus-tr3337 and gus-wt genes were independently cloned in a plant expression vector and introduced into Arabidopsis thaliana. With 4-MUG as a substrate, plants containing the gus-wt gene showed no detectable β-glucuronidase activity after exposure to 60°C for 10 min, while those hosting the gus-tr3337 gene retained 70% or 50% activity after exposure to 80°C for 10 min or 30 min, respectively. Similarly, in vivo β-glucuronidase activity could be demonstrated by using X-GLUC as a substrate in transgenic Arabidopsis plants hosting the gus-tr3337 gene that were exposed to 80°C for up to 30 min. Thus, the thermostability of GUS-TR3337 can be exploited to distinguish between endogenous and transgenic β-glucuronidase activity, which is a welcome improvement in its use as a reporter.

  1. Two domain-disrupted hda6 alleles have opposite epigenetic effects on transgenes and some endogenous targets

    KAUST Repository

    Zhang, ShouDong

    2015-12-15

    HDA6 is a RPD3-like histone deacetylase. In Arabidopsis, it mediates transgene and some endogenous target transcriptional gene silencing (TGS) via histone deacetylation and DNA methylation. Here, we characterized two hda6 mutant alleles that were recovered as second-site suppressors of the DNA demethylation mutant ros1–1. Although both alleles derepressed 35S::NPTII and RD29A::LUC in the ros1–1 background, they had distinct effects on the expression of these two transgenes. In accordance to expression profiles of two transgenes, the alleles have distinct opposite methylation profiles on two reporter gene promoters. Furthermore, both alleles could interact in vitro and in vivo with the DNA methyltransferase1 with differential interactive strength and patterns. Although these alleles accumulated different levels of repressive/active histone marks, DNA methylation but not histone modifications in the two transgene promoters was found to correlate with the level of derepression of the reporter genes between the two had6 alleles. Our study reveals that mutations in different domains of HDA6 convey different epigenetic status that in turn controls the expression of the transgenes as well as some endogenous loci.

  2. Mutational effects of γ-rays and carbon ion beams on Arabidopsis seedlings

    OpenAIRE

    Yoshihara, Ryouhei; Nozawa, Shigeki; Hase, Yoshihiro; Narumi, Issay; Hidema, Jun; Sakamoto, Ayako N

    2013-01-01

    To assess the mutational effects of radiation on vigorously proliferating plant tissue, the mutation spectrum was analyzed with Arabidopsis seedlings using the plasmid-rescue method. Transgenic plants containing the Escherichia coli rpsL gene were irradiated with γ-rays and carbon ion beams (320-MeV 12C6+), and mutations in the rpsL gene were analyzed. Mutant frequency increased significantly following irradiation by γ-rays, but not by 320-MeV 12C6+. Mutation spectra showed that both radiatio...

  3. Map-based cloning of a gene controlling Omega-3 fatty acid desaturation in Arabidopsis

    Energy Technology Data Exchange (ETDEWEB)

    Arondel, V.; Lemieux, B.; Hwang, I. [Michigan State Univ., East Lansing, MI (United States)] [and others

    1992-11-20

    A gene from the flowering plant Arabidopsis thaliana that encodes an omega-3 desaturase was cloned on the basis of the genetic map position of a mutation affecting membrane and storage lipid fatty acid composition. Yeast artificial chromosomes covering the genetic locus were identified and used to probe a seed complementary DNA library. A complementary DNA clone for the desaturase was identified and introduced into roots of both wild-type and mutant plants by Ti plasmid-mediated transformation. Transgenic tissues of both mutant and wild-type plants had significantly increased amounts of the fatty acid produced by this desaturase. 24 refs., 2 figs., 1 tabs.

  4. Transgenic crop-mite interactions

    Czech Academy of Sciences Publication Activity Database

    Zemek, Rostislav

    France : IOBC/WPRS, 2007 - (Weintraub, P.), s. 155-160 ISBN 92-9067-200-3. [Meeting of IOBC study group "Integrated Control of Plant-feeding Mites". Jerusalem (IL), 12.03.2007-14.03.2007] R&D Projects: GA AV ČR IAA6007303 Institutional research plan: CEZ:AV0Z50070508 Keywords : GMO * transgenic plants * mites Subject RIV: GF - Plant Pathology, Vermin, Weed, Plant Protection

  5. Does ploidy level directly control cell size? Counterevidence from Arabidopsis genetics.

    Directory of Open Access Journals (Sweden)

    Hirokazu Tsukaya

    Full Text Available Ploidy level affects cell size in many organisms, and ploidy-dependent cell enlargement has been used to breed many useful organisms. However, how polyploidy affects cell size remains unknown. Previous studies have explored changes in transcriptome data caused by polyploidy, but have not been successful. The most naïve theory explaining ploidy-dependent cell enlargement is that increases in gene copy number increase the amount of protein, which in turn increases the cell volume. This hypothesis can be evaluated by examining whether any strains, mutants, or transgenics show the same cell size before and after a tetraploidization event. I performed this experiment by tetraploidizing various mutants and transgenics of Arabidopsis thaliana, which show a wide range in cell size, and found that the ploidy-dependent increase in cell volume is genetically regulated. This result is not in agreement with the theory described above.

  6. Transgenic mouse offspring generated by ROSI.

    Science.gov (United States)

    Moreira, Pedro; Pérez-Cerezales, Serafín; Laguna, Ricardo; Fernández-Gonzalez, Raúl; Sanjuanbenito, Belén Pintado; Gutiérrez-Adán, Alfonso

    2016-01-01

    The production of transgenic animals is an important tool for experimental and applied biology. Over the years, many approaches for the production of transgenic animals have been tried, including pronuclear microinjection, sperm-mediated gene transfer, transfection of male germ cells, somatic cell nuclear transfer and the use of lentiviral vectors. In the present study, we developed a new transgene delivery approach, and we report for the first time the production of transgenic animals by co-injection of DNA and round spermatid nuclei into non-fertilized mouse oocytes (ROSI). The transgene used was a construct containing the human CMV immediate early promoter and the enhanced GFP gene. With this procedure, 12% of the live offspring we obtained carried the transgene. This efficiency of transgenic production by ROSI was similar to the efficiency by pronuclear injection or intracytoplasmic injection of male gamete nuclei (ICSI). However, ICSI required fewer embryos to produce the same number of transgenic animals. The expression of Egfp mRNA and fluorescence of EGFP were found in the majority of the organs examined in 4 transgenic lines generated by ROSI. Tissue morphology and transgene expression were not distinguishable between transgenic animals produced by ROSI or pronuclear injection. Furthermore, our results are of particular interest because they indicate that the transgene incorporation mediated by intracytoplasmic injection of male gamete nuclei is not an exclusive property of mature sperm cell nuclei with compact chromatin but it can be accomplished with immature sperm cell nuclei with decondensed chromatin as well. The present study also provides alternative procedures for transgene delivery into embryos or reconstituted oocytes. PMID:26498042

  7. Arabidopsis EDT1/HDG11 improves drought and salt tolerance in cotton and poplar and increases cotton yield in the field.

    Science.gov (United States)

    Yu, Lin-Hui; Wu, Shen-Jie; Peng, Yi-Shu; Liu, Rui-Na; Chen, Xi; Zhao, Ping; Xu, Ping; Zhu, Jian-Bo; Jiao, Gai-Li; Pei, Yan; Xiang, Cheng-Bin

    2016-01-01

    Drought and salinity are two major environmental factors limiting crop production worldwide. Improvement of drought and salt tolerance of crops with transgenic approach is an effective strategy to meet the demand of the ever-growing world population. Arabidopsis ENHANCED DROUGHT TOLERANCE1/HOMEODOMAIN GLABROUS11 (AtEDT1/HDG11), a homeodomain-START transcription factor, has been demonstrated to significantly improve drought tolerance in Arabidopsis, tobacco, tall fescue and rice. Here we report that AtHDG11 also confers drought and salt tolerance in upland cotton (Gossypium hirsutum) and woody plant poplar (Populus tomentosa Carr.). Our results showed that both the transgenic cotton and poplar exhibited significantly enhanced tolerance to drought and salt stress with well-developed root system. In the leaves of the transgenic cotton plants, proline content, soluble sugar content and activities of reactive oxygen species-scavenging enzymes were significantly increased after drought and salt stress compared with wild type. Leaf stomatal density was significantly reduced, whereas stomatal and leaf epidermal cell size were significantly increased in both the transgenic cotton and poplar plants. More importantly, the transgenic cotton showed significantly improved drought tolerance and better agronomic performance with higher cotton yield in the field both under normal and drought conditions. These results demonstrate that AtHDG11 is not only a promising candidate for crops improvement but also for woody plants. PMID:25879154

  8. Defining the Functional Network of Epigenetic Regulators in Arabidopsis thaliana

    Institute of Scientific and Technical Information of China (English)

    Chongyuan Luo; Brittany G.Durgin; Naohide Watanabe; Eric Lam

    2009-01-01

    Development of ChiP-chip and ChlP-seq technologies has allowed genome-wide high-resolution profiling of chromatin-associated marks and binding sites for epigenetic regulators.However,signals for directing epigenetic modi fiers to their target sites are not understood.In this paper,we tested the hypothesis that genome location can affect the involvement of epigenetic regulators using Chromatin Charting (CC) Lines,which have an identical transgene construct inserted at different locations in the Arabidopsis genome.Four CC lines that showed evidence for epigenetic silencing of the luciferase reporter gene were transformed with RNAi vectors individually targeting epigenetic regulators LHP1,MOM1,CMT3,DRD1,DRM2,SUVH2,CLF,and HD1.Involvement of a particular epigenetic regulator in silencing the transgene locus in a CC line was determined by significant alterations in luciferase expression after suppression of the regulator's expression.Our results suggest that the targeting of epigenetic regulators can be influenced by genome location as well as sequence context.In addition,the relative importance of an epigenetic regulator can be influenced by tissue identity.We also report a novel approach to predict interactions between epigenetic regulators through clustering analysis of the regulators using alterations in gene expression of putative downstream targets,including endogenous loci and transgenes,in epigenetic mutants or RNAi lines.Our data support the existence of a complex and dynamic network of epigenetic regulators that serves to coordinate and control global gene expression in higher plants.

  9. Irregular Morphing for Real-Time Rendering of Large Terrain

    Science.gov (United States)

    Kalem, Sid'Ali; Kourgli, Assia

    2016-06-01

    The following paper proposes an alternative approach to the real-time adaptive triangulation problem. A new region-based multi-resolution approach for terrain rendering is described which improves on-the-fly the distribution of the density of triangles inside the tile after selecting appropriate Level-Of-Detail by an adaptive sampling. This proposed approach organizes the heightmap into a QuadTree of tiles that are processed independently. This technique combines the benefits of both Triangular Irregular Network approach and region-based multi-resolution approach by improving the distribution of the density of triangles inside the tile. Our technique morphs the initial regular grid of the tile to deformed grid in order to minimize approximation error. The proposed technique strives to combine large tile size and real-time processing while guaranteeing an upper bound on the screen space error. Thus, this approach adapts terrain rendering process to local surface characteristics and enables on-the-fly handling of large amount of terrain data. Morphing is based-on the multi-resolution wavelet analysis. The use of the D2WT multi-resolution analysis of the terrain height-map speeds up processing and permits to satisfy an interactive terrain rendering. Tests and experiments demonstrate that Haar B-Spline wavelet, well known for its properties of localization and its compact support, is suitable for fast and accurate redistribution. Such technique could be exploited in client-server architecture for supporting interactive high-quality remote visualization of very large terrain.

  10. Expression of a Carrot 36 kD Antifreeze Protein Gene Improves Cold Stress Tolerance in Transgenic Tobacco

    Institute of Scientific and Technical Information of China (English)

    2005-01-01

    Antifreeze proteins (AFPs) enable organisms to survive under cold conditions, and have great potential in improving cold tolerance of cold-sensitive plants. In order to determine whether expression of the carrot 36 kD antifreeze protein gene confers improved cold-resistant properties to plant tissues, we tried to obtain transgenic tobacco plants which expressed the antifreeze protein. Cold, salt, and drought induced promoter Prd29A was cloned using PCR from Arabidopsis. Two plant expression vectors based on pBI121 were constructed with CaMV35S:AFP and Prd29A:AFP. Tobacco plantlets were transformed by Agrobacterium-medicated transformation. PCR and Southern blotting demonstrated that the carrot 36 kD afp gene was successfully integrated into the genomes of transformed plantlets. The expression of the afp gene in transgenic plants led to improved tolerance to cold stress.However, the use of the strong constitutive 35S cauliflower mosaic virus (CaMV) promoter to drive expression of afp also resulted in growth retardation under normal growing conditions. In contrast, the expression of afp driven by the stress-inducible Prd29A promoter from Arabidopsis gave rise to minimal effects on plant growth while providing an increased tolerance to cold stress condition (2℃). The results demonstrated the prospect of using Prd29A-AFP transgenic plants in cold-stressed conditions that will in turn benefit agriculture.

  11. Practical rendering and computation with Direct3D 11

    CERN Document Server

    Zink, Jason; Hoxley, Jack

    2011-01-01

    Practical Rendering and Computation with Direct3D 11 packs in documentation and in-depth coverage of basic and high-level concepts related to using Direct 3D 11 and is a top pick for any serious programming collection. … perfect for a wide range of users. Any interested in computation and multicore models will find this packed with examples and technical applications.-Midwest Book Review, October 2011The authors have generously provided us with an optimal blend of concepts and philosophy, illustrative figures to clarify the more difficult points, and source code fragments to make the ideas con

  12. Horse-shoe lung-rediscovered via volume rendered images

    Directory of Open Access Journals (Sweden)

    Alpa Bharati

    2013-01-01

    Full Text Available Horseshoe lung, usually associated with pulmonary venolobar syndrome, is a rare congenital anomaly involving the fusion of the postero-basal segments of the right and left lungs across the midline. The fused segment or the isthmus lies posterior to the pericardium and anterior to the aorta.The associated pulmonary venolobar syndrome involves anomalous systemic arterial supply and anomlaous systemic venous drainage of the right lung. With the advent of MDCT imaging, we can diagnose this rare condition as well all its associated anomalies non-invasively. Volume-rendered techniques greatly simplify the complex anatomy and provide easy understanding of the same.

  13. Beaming teaching application: recording techniques for spatial xylophone sound rendering

    DEFF Research Database (Denmark)

    Markovic, Milos; Madsen, Esben; Olesen, Søren Krarup; Hoffmann, Pablo F.; Hammershøi, Dorte

    played at student's location is required at teacher's site. This paper presents a comparison of different recording techniques for a spatial xylophone sound rendering. Directivity pattern of the xylophone was measured and spatial properties of the sound field created by a xylophone as a distributed sound...... source were analyzed. Xylophone recordings were performed using different microphone configurations: one and two-channel recording setups are implemented. Recordings were carried out in standard listening room and in an anechoic chamber. Differences between anechoic and reverberant xylophone sound for...

  14. An example of quantum imaging: rendering an object undetectable

    CERN Document Server

    Ataman, Stefan

    2016-01-01

    In this paper we propose and analyse a Gedankenexperiment involving three non-linear crystals and two objects inserted in the idler beams. We show that, besides the behaviour that can be extrapolated from previous experiments involving two crystals and one object, we are able to predict a new effect: under certain circumstances, one of the objects can be rendered undetectable to any single detection rate on the signal photons with discarded idler photons. This effect could find applications in future developments of quantum imaging techniques.

  15. Distributed virtual reality system based on hybrid rendering

    Institute of Scientific and Technical Information of China (English)

    2000-01-01

    A distributed virtual reality system is presented based on a hybrid rendering scheme. This system first predicts the camera position of the next key frame in real-time according to the tendency of the current camera movement. The predicted key frame is then generated using a geometry-based algorithm. Finally, a real-time backward image warping algorithm is employed to create a smooth transition between the two adjacent key frames. Since the ren dering procedure can be divided into two independent steps, this system can be efficiently implemented in distributed mode.

  16. A transgenic approach to controlling wheat seed dormancy level by using Triticeae DOG1-like genes.

    Science.gov (United States)

    Ashikawa, Ikuo; Mori, Masahiko; Nakamura, Shingo; Abe, Fumitaka

    2014-08-01

    Seed dormancy is an important agronomic trait: low levels can cause premature germination, while too much can inhibit uniform germination. As an approach to controlling the seed dormancy level in crops, we used Triticeae DOG1-like genes as transgenes. DOG1 is an Arabidopsis gene that underlies natural variation in seed dormancy. We previously showed that although their sequence similarities to DOG1 were low, some cereal DOG1-like genes enhanced seed dormancy in Arabidopsis. Here, we introduced two DOG1-like genes, TaDOG1L4 from wheat and HvDOG1L1 from barley, individually into the wheat cultivar Fielder. Their overexpression under the control of a maize ubiquitin promoter enhanced the seed dormancy level while leaving other traits unchanged. TaDOG1L4 was more effective than HvDOG1L1, which accords with the previously revealed difference in the effectiveness of these two genes in Arabidopsis seed dormancy. Knockdown of endogenous TaDOG1L4 in Fielder using double-strand RNA interference decreased the seed dormancy level by several tens of percent. This result indicates that some degree of seed dormancy inherent in wheat is imparted by DOG1-like genes. PMID:24752830

  17. Overexpression of OsRAA1 promotes flowering and hypocotyls elongation in Arabidopsis

    Institute of Scientific and Technical Information of China (English)

    WANG JinLan; CHONG Kang; XU YunYuan

    2009-01-01

    Previously,OsRAA1,an AtFPF1 homologue gene,was found to play an important role in modulating rice root development.In the current study,OsRAA1 was overexpressed in Arabidopsis,and the transgenic plants showed early flowering and elongated hypocotyl phenotypes as compared with the wild-type under white-light conditions.The hypocotyls of transgenic lines were twice as long as those of wild-type plants under red-light conditions but were indistinguishable from those of the wild-type under blue and far-red light and darkness.In addition,the phenotypes of AtFPF1 transgenic lines were similar to those of OsRAA1 transgenic lines.These results suggested that OsRAA1/AtFPF1 protein is involved in regulating flowering time and plays an important role in the inhibition of hypocotyl elongation under continuous red light.The functions were preserved during the evolution.

  18. Integration mechanisms of transgenes and population fitness of GH transgenic fish

    Institute of Scientific and Technical Information of China (English)

    2010-01-01

    It has been more than 20 years since the first batch of transgenic fish was produced. Five stable germ-line transmitted growth hormone (GH) transgenic fish lines have been generated. This paper reviews the mechanisms of integration and gene targeting of the transgene, as well as the viability, reproduction and transgenic approaches for the reproductive containment of GH-transgenic fish. Further, we propose that it should be necessary to do the following studies, in particularly, of the breeding of transgenic fish: to assess the fitness of transgenic fish in an aqueous environment with a large space and a complex structure; and to develop a controllable on-off strategy of reproduction in transgenic fish.

  19. Relevance of BAC transgene copy number in mice: transgene copy number variation across multiple transgenic lines and correlations with transgene integrity and expression

    OpenAIRE

    Chandler, Kelly J.; Chandler, Ronald L.; Broeckelmann, Eva M.; HOU, YUE; Southard-Smith, E. Michelle; Mortlock, Douglas P.

    2007-01-01

    Bacterial artificial chromosomes (BACs) are excellent tools for manipulating large DNA fragments and, as a result, are increasingly utilized to engineer transgenic mice by pronuclear injection. The demand for BAC transgenic mice underscores the need for careful inspection of BAC integrity and fidelity following transgenesis, which may be crucial for interpreting transgene function. Thus, it is imperative that reliable methods for assessing these parameters are available. However, there are li...

  20. Non-Photorealistic Rendering in Chinese Painting of Animals

    Institute of Scientific and Technical Information of China (English)

    2002-01-01

    A set of algorithms is proposed in this paper to automatically transform 3D animal models to Chinese painting style. Inspired by real painting process in Chinese painting of animals, we divide the whole rendering process into two parts: borderline stroke making and interior shading. In borderline stroke making process we first find 3D model silhouettes in real-time depending on the viewing direction of a user. After retrieving silhouette information from all model edges, a stroke linking mechanism is applied to link these independent edges into a long stroke. Finally we grow a plain thin silhouette line to a stylus stroke with various widths at each control point and a 2D brush model is combined with it to simulate a Chinese painting stroke. In the interior shading pipeline, three stages are used to convert a Gouraud-shading image to a Chinese painting style image: color quantization, ink diffusion and box filtering. The color quantization stage assigns all pixels in an image into four color levels and each level represents a color layer in a Chinese painting. Ink diffusion stage is used to transfer inks and water between different levels and to grow areas in an irregular way. The box filtering stage blurs sharp borders between different levels to embellish the appearance of final interior shading image. In addition to automatic rendering, an interactive Chinese painting system which is equipped with friendly input devices can be also combined to generate more artistic Chinese painting images manually.

  1. Characterization of antibiotic-resistant bacteria in rendered animal products.

    Science.gov (United States)

    Hofacre, C L; White, D G; Maurer, J J; Morales, C; Lobsinger, C; Hudson, C

    2001-01-01

    Antibiotics are used in food animal production to treat diseases and also to improve performance. Antibiotics are not used on all farms, and antibiotic resistance is occasionally found on farms that do not use antibiotics. Rendered animal protein products are often included in poultry feeds and could potentially serve as a source of antibiotic-resistant bacteria. One hundred sixty-five rendered animal protein products from cattle, poultry, and fish were aseptically collected from poultry feed mills. Fifty-five percent of the poultry meal samples had detectable levels of gram-negative bacteria ranging from 40 to 10,440 colony-forming units/g of sample. Poultry meal and meat and bone meal had the greatest number of samples with bacteria resistant to five or more antibiotics. A high percentage of feed samples (85%) contained bacteria resistant to amoxicillin, ampicillin, clavulanic acid, or cephalothin, whereas few samples contained bacteria resistant to ciprofloxacin, kanamycin, or trimethoprim/sulfamethoxazole. Acinetobacter calcoaceticus, Citrobacter freundii, and Enterobacter cloacae were the most commonly isolated antibiotic-resistant bacteria. Isolation for Salmonella was also performed, with 14% of the meat and bone meal samples containing Salmonella sp. Only one of the meat and bone meal isolates, Salmonella livingstone, was resistant to five or more antibiotics. Many of the antibiotic-resistant bacteria contained integrons, genetic elements that mediate multiple drug resistance. PMID:11785899

  2. Haptic Rendering in Interactive Applications Developed with Commodity Physics Engine

    Directory of Open Access Journals (Sweden)

    Kup-Sze Choi

    2011-04-01

    Full Text Available Availability of commodity physics engines such as PhysX’s nVidia has significantly reduced the effort required for developing interactive applications concerning the simulation of the physical world. However, it becomes a problem when force feedback is needed since the addition of haptic rendering into these applications is non-trivial. The issues include the high haptic update rate and the inaccessibility of force data in the physics engine. In the paper, we tackle the first issue by mediating the update-rate disparity between haptic rendering and other processes by data buffering, and the second issue by calculating the force feedback indirectly using the engine’s collision geometry data. The major benefit of these techniques is that they enable a homogeneous development environment where the same engine can be used for both the physics and haptic simulation. Furthermore, integration of force feedback into physics-engine based applications would not introduce significant changes into developer’s codebase. The proposed techniques have potential to streamline the development of demanding applications such as virtual surgical simulation and immersive computer gaming.

  3. Sparse PDF Volumes for Consistent Multi-Resolution Volume Rendering

    KAUST Repository

    Sicat, Ronell

    2014-12-31

    This paper presents a new multi-resolution volume representation called sparse pdf volumes, which enables consistent multi-resolution volume rendering based on probability density functions (pdfs) of voxel neighborhoods. These pdfs are defined in the 4D domain jointly comprising the 3D volume and its 1D intensity range. Crucially, the computation of sparse pdf volumes exploits data coherence in 4D, resulting in a sparse representation with surprisingly low storage requirements. At run time, we dynamically apply transfer functions to the pdfs using simple and fast convolutions. Whereas standard low-pass filtering and down-sampling incur visible differences between resolution levels, the use of pdfs facilitates consistent results independent of the resolution level used. We describe the efficient out-of-core computation of large-scale sparse pdf volumes, using a novel iterative simplification procedure of a mixture of 4D Gaussians. Finally, our data structure is optimized to facilitate interactive multi-resolution volume rendering on GPUs.

  4. Direct Volume Rendering with Shading via Three-Dimensional Textures

    Science.gov (United States)

    Van Gelder, Allen; Kim, Kwansik

    1996-01-01

    A new and easy-to-implement method for direct volume rendering that uses 3D texture maps for acceleration, and incorporates directional lighting, is described. The implementation, called Voltx, produces high-quality images at nearly interactive speeds on workstations with hardware support for three-dimensional texture maps. Previously reported methods did not incorporate a light model, and did not address issues of multiple texture maps for large volumes. Our research shows that these extensions impact performance by about a factor of ten. Voltx supports orthographic, perspective, and stereo views. This paper describes the theory and implementation of this technique, and compares it to the shear-warp factorization approach. A rectilinear data set is converted into a three-dimensional texture map containing color and opacity information. Quantized normal vectors and a lookup table provide efficiency. A new tesselation of the sphere is described, which serves as the basis for normal-vector quantization. A new gradient-based shading criterion is described, in which the gradient magnitude is interpreted in the context of the field-data value and the material classification parameters, and not in isolation. In the rendering phase, the texture map is applied to a stack of parallel planes, which effectively cut the texture into many slabs. The slabs are composited to form an image.

  5. Physically Based Rendering in the Nightshade NG Visualization Platform

    Science.gov (United States)

    Berglund, Karrie; Larey-Williams, Trystan; Spearman, Rob; Bogard, Arthur

    2015-01-01

    This poster describes our work on creating a physically based rendering model in Nightshade NG planetarium simulation and visualization software (project website: NightshadeSoftware.org). We discuss techniques used for rendering realistic scenes in the universe and dealing with astronomical distances in real time on consumer hardware. We also discuss some of the challenges of rewriting the software from scratch, a project which began in 2011.Nightshade NG can be a powerful tool for sharing data and visualizations. The desktop version of the software is free for anyone to download, use, and modify; it runs on Windows and Linux (and eventually Mac). If you are looking to disseminate your data or models, please stop by to discuss how we can work together.Nightshade software is used in literally hundreds of digital planetarium systems worldwide. Countless teachers and astronomy education groups run the software on flat screens. This wide use makes Nightshade an effective tool for dissemination to educators and the public.Nightshade NG is an especially powerful visualization tool when projected on a dome. We invite everyone to enter our inflatable dome in the exhibit hall to see this software in a 3D environment.

  6. Fast polyhedral cell sorting for interactive rendering of unstructured grids

    Energy Technology Data Exchange (ETDEWEB)

    Combra, J; Klosowski, J T; Max, N; Silva, C T; Williams, P L

    1998-10-30

    Direct volume rendering based on projective methods works by projecting, in visibility order, the polyhedral cells of a mesh onto the image plane, and incrementally compositing the cell's color and opacity into the final image. Crucial to this method is the computation of a visibility ordering of the cells. If the mesh is ''well-behaved'' (acyclic and convex), then the MPVO method of Williams provides a very fast sorting algorithm; however, this method only computes an approximate ordering in general datasets, resulting in visual artifacts when rendered. A recent method of Silva et al. removed the assumption that the mesh is convex, by means of a sweep algorithm used in conjunction with the MPVO method; their algorithm is substantially faster than previous exact methods for general meshes. In this paper we propose a new technique, which we call BSP-XMPVO, which is based on a fast and simple way of using binary space partitions on the boundary elements of the mesh to augment the ordering produced by MPVO. Our results are shown to be orders of magnitude better than previous exact methods of sorting cells.

  7. Morphological pyramids in multiresolution MIP rendering of large volume data : Survey and new results

    NARCIS (Netherlands)

    Roerdink, Jos B.T.M.

    2005-01-01

    We survey and extend nonlinear signal decompositions based on morphological pyramids, and their application to multiresolution maximum intensity projection (MIP) volume rendering with progressive refinement and perfect reconstruction. The structure of the resulting multiresolution rendering algorith

  8. Multistage epidermal carcinogenesis in transgenic mice: cooperativity and paradox.

    Science.gov (United States)

    Greenhalgh, D A; Wang, X J; Roop, D R

    1996-04-01

    Skin cancer is one of the most prevalent forms of human neoplasia with a frequency approaching that of all other neoplasms combined. Given this alarming statistic, which may be further exacerbated by increased ultraviolet B irradiation from ozone depletion, it is vital that realistic, relevant model systems are developed to increase our understanding of the underlying molecular mechanisms of carcinogenesis that result in or evaluate new treatment modalities. Toward this goal, the ability to stably introduce genes into the germline of mice has greatly enhanced prospects for generation of transgenic animal models of multistage molecular carcinogenesis. Moreover, when genes are combined with regulatory sequences that target their expression to specific tissues, investigators are able to study neoplasia both in the context of living organisms and in the tissues suspected of being the targets of these genes. The epidermis is an attractive tissue for targeted gene expression; not only is it a model for epithelial diseases in general, but the accessibility of the epidermis allows easy detection of progressive pathological changes that result from transgene expression and facilitates assessment of the potential role played by environmental factors. We have developed a targeting vector based on the human keratin gene (HK1), which is expressed exclusively in the epidermis of transgenic mice, at a late stage in development and in both basal and differentiated cells. Through the use of this targeting ability, rasHa, fos, and TGF alpha transgenic mice have been developed that exhibit preneoplastic epidermal hyperplasia and hyperkeratosis, and later benign, regression prone papillomas. Together, coexpression of two oncogenes cooperated to give autonomous papillomas, which possessed the phenotypic stability to allow assessment of a third genetic event, namely loss of the p53 tumor suppressor gene, via mating with p53 knockout mice. Loss of p53 expression, however, identified a

  9. Overexpression of the IbMYB1 gene in an orange-fleshed sweet potato cultivar produces a dual-pigmented transgenic sweet potato with improved antioxidant activity.

    Science.gov (United States)

    Park, Sung-Chul; Kim, Yun-Hee; Kim, Sun Ha; Jeong, Yu Jeong; Kim, Cha Young; Lee, Joon Seol; Bae, Ji-Yeong; Ahn, Mi-Jeong; Jeong, Jae Cheol; Lee, Haeng-Soon; Kwak, Sang-Soo

    2015-04-01

    The R2R3-type protein IbMYB1 is a key regulator of anthocyanin biosynthesis in the storage roots of sweet potato [Ipomoea batatas (L.) Lam]. Previously, we demonstrated that IbMYB1 expression stimulated anthocyanin pigmentation in tobacco leaves and Arabidopsis. Here, we generated dual-pigmented transgenic sweet potato plants that accumulated high levels of both anthocyanins and carotenoids in a single sweet potato storage root. An orange-fleshed cultivar with high carotenoid levels was transformed with the IbMYB1 gene under the control of either the storage root-specific sporamin 1 (SPO1) promoter or the oxidative stress-inducible peroxidase anionic 2 (SWPA2) promoter. The SPO1-MYB transgenic lines exhibited higher anthocyanin levels in storage roots than empty vector control (EV) or SWPA2-MYB plants, but carotenoid content was unchanged. SWPA2-MYB transgenic lines exhibited higher levels of both anthocyanin and carotenoids than EV plants. Analysis of hydrolyzed anthocyanin extracts indicated that cyanidin and peonidin predominated in both overexpression lines. Quantitative reverse transcription-polymerase chain reaction analysis demonstrated that IbMYB1 expression in both IbMYB1 transgenic lines strongly induced the upregulation of several genes in the anthocyanin biosynthetic pathway, whereas the expression of carotenoid biosynthetic pathway genes varied between transgenic lines. Increased anthocyanin levels in transgenic plants also promoted the elevation of proanthocyanidin and total phenolic levels in fresh storage roots. Consequently, all IbMYB1 transgenic plants displayed much higher antioxidant activities than EV plants. In field cultivations, storage root yields varied between the transgenic lines. Taken together, our results indicate that overexpression of IbMYB1 is a highly promising strategy for the generation of transgenic plants with enhanced antioxidant capacity. PMID:25220246

  10. Arabidopsis Vacuolar Pyrophosphatase gene (AVP1) induces drought and salt tolerance in Nicotiana tabacum plants (abstract)

    International Nuclear Information System (INIS)

    Drought and salinity are global problems. In Pakistan these problems are increasing to an alarming situation due to low rain-fall and bad agricultural practices. Salt and drought stress shows a high degree of similarity with respect to physiological, biochemical, molecular and genetic effects. This is due to the fact that sub-lethal salt-stress condition is ultimately an osmotic effect which is apparently similar to that brought in by water deficit. Genetic engineering allows the re-introduction of plant genes into their genomes by increasing their expression level. Plant vacuoles play a central role in cellular mechanisms of adaptation to salinity and drought stresses. In principle, increased vacuolar solute accumulation should have a positive impact in the adaptation of plants to salinity and drought. The active transport of the solutes depends on the proton gradients established by proton pumps. We have over expressed Arabidopsis gene AVP1 (Arabidopsis thaliana vacuolar pyro phosphatase H/sup +/ pump) to increase drought/salt tolerance in tobacco. The AVP1 ORF with a tandem repeat of 358 promoter was cloned in pPZP212 vector and Agrobacterium-mediated transformation was performed. Transgenic plants were selected on plant nutrient agar medium supplemented with 50 mg/liter kanamycin. Transgenic plants were confirmed for transfer of genes by AVP1 and nptll gene specific PCR and Southern hybridization. AVP1 transgenic plants were screened for salt tolerance by providing NaCl solution in addition to nutrient solution. AVP1 transgenic plants showed tolerance up to 300 mM NaCl as compared to control which died ten days after 200 mM NaCl. Sodium and potassium were measured in salt treated and control plants. Results showed that sodium ion uptake in the salt treated transgenic plants was four times more as compared to wild type. This remarkable increase in Na/sup +/ ion uptake indicates that AVP1 vacuole proton pumps are actively involved in the transport of Na

  11. Improvements in the transformation of Arabidopsis thaliana C24 leaf-discs by Agrobacterium tumefaciens

    DEFF Research Database (Denmark)

    van der Graaff, Eric; Hooykaas, P J

    1996-01-01

    We report here an efficient Arabidopsis leafdisc transformation protocol yielding an average transformation frequency of 1.6 transgenic shoots per leaf explant 4 weeks after the bacterial infection period. Subsequent cultivation in vitro is such that a high percentage (85-90%) of the primary tran...... harboring an activator T-DNA construct in a gene tagging approach to isolate genes involved in morphogenesis and auxin signal transduction....

  12. The Ca(2+) status of the endoplasmic reticulum is altered by induction of calreticulin expression in transgenic plants

    Science.gov (United States)

    Persson, S.; Wyatt, S. E.; Love, J.; Thompson, W. F.; Robertson, D.; Boss, W. F.; Brown, C. S. (Principal Investigator)

    2001-01-01

    To investigate the endoplasmic reticulum (ER) Ca(2+) stores in plant cells, we generated tobacco (Nicotiana tabacum; NT1) suspension cells and Arabidopsis plants with altered levels of calreticulin (CRT), an ER-localized Ca(2+)-binding protein. NT1 cells and Arabidopsis plants were transformed with a maize (Zea mays) CRT gene in both sense and antisense orientations under the control of an Arabidopsis heat shock promoter. ER-enriched membrane fractions from NT1 cells were used to examine how altered expression of CRT affects Ca(2+) uptake and release. We found that a 2.5-fold increase in CRT led to a 2-fold increase in ATP-dependent (45)Ca(2+) accumulation in the ER-enriched fraction compared with heat-shocked wild-type controls. Furthermore, after treatment with the Ca(2+) ionophore ionomycin, ER microsomes from NT1 cells overproducing CRT showed a 2-fold increase in the amount of (45)Ca(2+) released, and a 2- to 3-fold increase in the amount of (45)Ca(2+) retained compared with wild type. These data indicate that altering the production of CRT affects the ER Ca(2+) pool. In addition, CRT transgenic Arabidopsis plants were used to determine if altered CRT levels had any physiological effects. We found that the level of CRT in heat shock-induced CRT transgenic plants correlated positively with the retention of chlorophyll when the plants were transferred from Ca(2+)-containing medium to Ca(2+)-depleted medium. Together these data are consistent with the hypothesis that increasing CRT in the ER increases the ER Ca(2+) stores and thereby enhances the survival of plants grown in low Ca(2+) medium.

  13. Cross-resistance to short residual sulfonylurea herbicides in transgenic tobacco plants.

    Science.gov (United States)

    Gabard, J M; Charest, P J; Iyer, V N; Miki, B L

    1989-10-01

    Transgenic Nicotiana tabacum plants, produced by Agrobacterium tumefaciens-mediated transformation with a mutant gene (csr1-1) coding for acetohydroxyacid synthase (AHAS) from a chlorsulfuron resistant Arabidopsis thaliana line GH50 (GW Haughn et al. [1988] Mol Gen Genet 211: 266-271; GW Haughn, C Somerville [1986] Mol Gen Genet 204: 430-434), were selected directly on 80 micrograms per liter (225 nanomolar) chlorsulfuron. The expression of csr-1 in two separate transgenic lines CHL-1 and CHL-2 was confirmed by biochemical and genetic analyses. The AHAS activity of GH50 and the equivalent component of AHAS activity in CHL-2 was resistant to three short residual sulfonylurea herbicides, DPX-M6316, DPX-A7881, and DPX-L5300, in addition to chlorsulfuron but not to the sulfonylurea CGA 131'036. Cross-resistance to the imidazolinones AC 263, 499, AC 252, 214, and AC 243,997 was not observed. Parallel observations were made on the inhibition of seedling growth in soil or on culture medium. The relevance of these findings for the application of transgenic plants in agriculture is discussed. PMID:16667071

  14. THE ACTIVITY OF ARABIDOSPIS DLL PROMOTER IN TRANSGENIC TOBACCO PLANTS UNDER WATER STRESS CONDITIONS

    Directory of Open Access Journals (Sweden)

    Zuzana Polóniová

    2014-02-01

    Full Text Available In this work we used the Cre/loxP recombination system to study the activity of the Arabidopsis DLL promoter under water stress treatment. For this, the T-DNA containing the Cre/loxP self-excision recombination cassette was introduced into tobacco genome via A. tumefaciens LBA 4404. The expression of the cre gene was regulated by the DLL promoter. On activity of the DLL the Cre recombinase was expected to remove Cre/loxP cassette. Transgenic nature of regenerated transgenic T0 tobacco plantlets was proved by GUS and PCR analyses. The selected 10 transgenic T0 plants were subjected to the water stress analyses under in vitro as well as under in vivo conditions. The osmotic stress experiments were performed with 10 % PEG and 100 mmol.l-1 mannitol (individually. The activity of the DLL was evaluated after 24 hours. For drought stress experiments, the watering was withheld for 10 days. The activity of the DLL was monitored using PCR approach. Under given abiotic stress conditions, no activity of the DLL was observed. The DLL promoter remained stable. It points out the DLL as the promoter with precise control of the gene expression with wide usability in plant biotechnology.

  15. Volume rendering: application in static field conformal radiosurgery

    Science.gov (United States)

    Bourland, J. Daniel; Camp, Jon J.; Robb, Richard A.

    1992-09-01

    Lesions in the head which are large or irregularly shaped present challenges for radiosurgical treatment by linear accelerator or other radiosurgery modalities. To treat these lesions we are developing static field, conformal stereotactic radiosurgery. In this procedure seven to eleven megavoltage x-ray beams are aimed at the target volume. Each beam is designed from the beam's-eye view, and has its own unique geometry: gantry angle, table angle, and shape which conforms to the projected cross-section of the target. A difficulty with this and other 3- D treatment plans is the visualization of the treatment geometry and proposed treatment plan. Is the target volume geometrically covered by the arrangement of beams, and is the dose distribution adequate? To answer these questions we have been investigating the use of ANALYZETM volume rendering to display the target anatomy and the resultant dose distribution.

  16. Depth remapping using seam carving for depth image based rendering

    Science.gov (United States)

    Tsubaki, Ikuko; Iwauchi, Kenichi

    2015-03-01

    Depth remapping is a technique to control depth range of stereo images. Conventional remapping which uses a transform function in the whole image has a stable characteristic, however it sometimes reduces the 3D appearance too much. To cope with this problem, a depth remapping method which preserves the details of depth structure is proposed. We apply seam carving, which is an effective technique for image retargeting, to depth remapping. An extended depth map is defined as a space-depth volume, and a seam surface which is a 2D monotonic and connected manifold is introduced. The depth range is reduced by removing depth values on the seam surface from the space-depth volume. Finally a stereo image pair is synthesized from the corrected depth map and an input color image by depth image based rendering.

  17. Real-Time Air Pollutants Rendering based on Image Processing

    Directory of Open Access Journals (Sweden)

    Demin Wang

    2011-11-01

    Full Text Available This paper presents a new method for realistic real-time rendering of air pollutants based on image processing. The air pollutants’ variable density can create many shapes of mist what can add a realistic environment to virtual scene. In order to achieve a realistic effect, we further enhance thus obtained air pollution data getting from monitor in spatial domain. In the proposed method we map the densities of air pollutants to different gray levels, and visualize them by blending those gray levels with background images. The proposed method can also visualize large-scale air pollution data from different viewpoints in real-time and provide the resulting image with any resolution theoretically, which is very important and favorable for the Internet transmission.

  18. Technologies Render Views of Earth for Virtual Navigation

    Science.gov (United States)

    2012-01-01

    On a December night in 1995, 159 passengers and crewmembers died when American Airlines Flight 965 flew into the side of a mountain while in route to Cali, Colombia. A key factor in the tragedy: The pilots had lost situational awareness in the dark, unfamiliar terrain. They had no idea the plane was approaching a mountain until the ground proximity warning system sounded an alarm only seconds before impact. The accident was of the kind most common at the time CFIT, or controlled flight into terrain says Trey Arthur, research aerospace engineer in the Crew Systems and Aviation Operations Branch at NASA s Langley Research Center. In situations such as bad weather, fog, or nighttime flights, pilots would rely on airspeed, altitude, and other readings to get an accurate sense of location. Miscalculations and rapidly changing conditions could contribute to a fully functioning, in-control airplane flying into the ground. To improve aviation safety by enhancing pilots situational awareness even in poor visibility, NASA began exploring the possibilities of synthetic vision creating a graphical display of the outside terrain on a screen inside the cockpit. How do you display a mountain in the cockpit? You have to have a graphics-powered computer, a terrain database you can render, and an accurate navigation solution, says Arthur. In the mid-1990s, developing GPS technology offered a means for determining an aircraft s position in space with high accuracy, Arthur explains. As the necessary technologies to enable synthetic vision emerged, NASA turned to an industry partner to develop the terrain graphical engine and database for creating the virtual rendering of the outside environment.

  19. Transcription-dependent silencing of inducible convergent transgenes in transgenic mice

    Directory of Open Access Journals (Sweden)

    Calero-Nieto Fernando J

    2010-01-01

    Full Text Available Abstract Background Silencing of transgenes in mice is a common phenomenon typically associated with short multi-copy transgenes. We have investigated the regulation of the highly inducible human granulocyte-macrophage colony-stimulating-factor gene (Csf2 in transgenic mice. Results In the absence of any previous history of transcriptional activation, this transgene was expressed in T lineage cells at the correct inducible level in all lines of mice tested. In contrast, the transgene was silenced in a specific subset of lines in T cells that had encountered a previous episode of activation. Transgene silencing appeared to be both transcription-dependent and mediated by epigenetic mechanisms. Silencing was accompanied by loss of DNase I hypersensitive sites and inability to recruit RNA polymerase II upon stimulation. This pattern of silencing was reflected by increased methylation and decreased acetylation of histone H3 K9 in the transgene. We found that silenced lines were specifically associated with a single pair of tail-to-tail inverted repeated copies of the transgene embedded within a multi-copy array. Conclusions Our study suggests that epigenetic transgene silencing can result from convergent transcription of inverted repeats which can lead to silencing of an entire multi-copy transgene array. This mechanism may account for a significant proportion of the reported cases of transgene inactivation in mice.

  20. Transgenic Papaya: Development, Release, Impact, and Challenges

    Science.gov (United States)

    Although the technology for developing virus-resistant transgenic plants through the use of the coat protein of a virus was unveiled twenty years ago, it is surprising to note that only a three virus-resistant plants (squash, potato, and papaya) have been commercialized in the U.S. The transgenic p...

  1. Transgenic Biofuel Feedstocks and Strategies for Biocontainment

    Science.gov (United States)

    There are several reasons to believe that transgenic plant feedstocks will be required to realize the full economic and environmental benefits of cellulosic and other biofuels. Much of the commercialization potential for the use of transgenic plant cellulosic feedstocks may be impacted by regulatio...

  2. A novel protective function for cytokinin in the light stress response is mediated by the Arabidopsis histidine kinase2 and Arabidopsis histidine kinase3 receptors.

    Science.gov (United States)

    Cortleven, Anne; Nitschke, Silvia; Klaumünzer, Marion; Abdelgawad, Hamada; Asard, Han; Grimm, Bernhard; Riefler, Michael; Schmülling, Thomas

    2014-03-01

    Cytokinins are plant hormones that regulate diverse processes in plant development and responses to biotic and abiotic stresses. In this study, we show that Arabidopsis (Arabidopsis thaliana) plants with a reduced cytokinin status (i.e. cytokinin receptor mutants and transgenic cytokinin-deficient plants) are more susceptible to light stress compared with wild-type plants. This was reflected by a stronger photoinhibition after 24 h of high light (approximately 1,000 µmol m(-2) s(-1)), as shown by the decline in maximum quantum efficiency of photosystem II photochemistry. Photosystem II, especially the D1 protein, is highly sensitive to the detrimental impact of light. Therefore, photoinhibition is always observed when the rate of photodamage exceeds the rate of D1 repair. We demonstrate that in plants with a reduced cytokinin status, the D1 protein level was strongly decreased upon light stress. Inhibition of the D1 repair cycle by lincomycin treatment indicated that these plants experience stronger photodamage. The efficiency of photoprotective mechanisms, such as nonenzymatic and enzymatic scavenging systems, was decreased in plants with a reduced cytokinin status, which could be a cause for the increased photodamage and subsequent D1 degradation. Additionally, slow and incomplete recovery in these plants after light stress indicated insufficient D1 repair. Mutant analysis revealed that the protective function of cytokinin during light stress depends on the Arabidopsis histidine KINASE2 (AHK2) and AHK3 receptors and the type B Arabidopsis response regulator1 (ARR1) and ARR12. We conclude that proper cytokinin signaling and regulation of specific target genes are necessary to protect leaves efficiently from light stress. PMID:24424319

  3. Ectopic expression of R3 MYB transcription factor gene OsTCL1 in Arabidopsis, but not rice, affects trichome and root hair formation

    Science.gov (United States)

    Zheng, Kaijie; Tian, Hainan; Hu, Qingnan; Guo, Hongyan; Yang, Li; Cai, Ling; Wang, Xutong; Liu, Bao; Wang, Shucai

    2016-01-01

    In Arabidopsis, a MYB-bHLH-WD40 (MBW) transcriptional activator complex activates the homeodomain protein gene GLABRA2 (GL2), leading to the promotion of trichome formation and inhibition of root hair formation. The same MBW complex also activates single-repeat R3 MYB genes. R3 MYBs in turn, play a negative feedback role by competing with R2R3 MYB proteins for binding bHLH proteins, thus blocking the formation of the MBW complex. By BLASTing the rice (Oryza sativa) protein database using the entire amino acid sequence of Arabidopsis R3 MYB transcription factor TRICHOMELESS1 (TCL1), we found that there are two genes in rice genome encoding R3 MYB transcription factors, namely Oryza sativa TRICHOMELESS1 (OsTCL1) and OsTCL2. Expressing OsTCL1 in Arabidopsis inhibited trichome formation and promoted root hair formation, and OsTCL1 interacted with GL3 when tested in Arabidopsis protoplasts. Consistent with these observations, expression levels of GL2, R2R3 MYB transcription factor gene GLABRA1 (GL1) and several R3 MYB genes were greatly reduced, indicating that OsTCL1 is functional R3 MYB. However, trichome and root hair formation in transgenic rice plants overexpressing OsTCL1 remained largely unchanged, and elevated expression of OsGL2 was observed in the transgenic rice plants, indicating that rice may use different mechanisms to regulate trichome formation. PMID:26758286

  4. A Parallel Pipelined Renderer for the Time-Varying Volume Data

    Science.gov (United States)

    Chiueh, Tzi-Cker; Ma, Kwan-Liu

    1997-01-01

    This paper presents a strategy for efficiently rendering time-varying volume data sets on a distributed-memory parallel computer. Time-varying volume data take large storage space and visualizing them requires reading large files continuously or periodically throughout the course of the visualization process. Instead of using all the processors to collectively render one volume at a time, a pipelined rendering process is formed by partitioning processors into groups to render multiple volumes concurrently. In this way, the overall rendering time may be greatly reduced because the pipelined rendering tasks are overlapped with the I/O required to load each volume into a group of processors; moreover, parallelization overhead may be reduced as a result of partitioning the processors. We modify an existing parallel volume renderer to exploit various levels of rendering parallelism and to study how the partitioning of processors may lead to optimal rendering performance. Two factors which are important to the overall execution time are re-source utilization efficiency and pipeline startup latency. The optimal partitioning configuration is the one that balances these two factors. Tests on Intel Paragon computers show that in general optimal partitionings do exist for a given rendering task and result in 40-50% saving in overall rendering time.

  5. Three-dimensional reconstructions of carotid bifurcation from CT images: evaluation of different rendering methods

    International Nuclear Information System (INIS)

    Three-dimensional computed tomographic angiography (3D-CTA) and digital subtraction angiography of the cervical carotid artery were performed bilaterally in 15 patients with suspected stenoses. A new semi-automatic segmentation and new rendering methods were used. The degree of stenosis of internal carotid arteries, as determined both by axial slices and 3D images (surface, integral, maximum-intensity-projection, and raysum-rendered images), was compared qualitatively and quantitatively to angiographic findings. In correlation to angiography, the accuracy in determining the stenosis classification of internal carotid arteries was of 97% for axial slices and 59-90% for 3D images, respectively. Raysum (pseudoradiograph) rendering was found to be the most reliable rendering method and gave the most similar results to angiography. The accuracy of all rendering methods was improved by applying calcification removing algorithm, with a statistically significant difference between surface rendering without plaque removal and raysum rendering using the removing algorithm. (orig.)

  6. Three-dimensional reconstructions of carotid bifurcation from CT images: evaluation of different rendering methods

    Energy Technology Data Exchange (ETDEWEB)

    Tarjan, Z. [Dept. of Radiology, Univ. Hospital of Trieste, Ospedale di Cattinara, Trieste (Italy); Pozzi Mucelli, F. [Dept. of Radiology, Univ. Hospital of Trieste, Ospedale di Cattinara, Trieste (Italy); Frezza, F. [Dept. of Radiology, Univ. Hospital of Trieste, Ospedale di Cattinara, Trieste (Italy); Pozzi Mucelli, R. [Dept. of Radiology, Univ. Hospital of Trieste, Ospedale di Cattinara, Trieste (Italy)

    1996-06-01

    Three-dimensional computed tomographic angiography (3D-CTA) and digital subtraction angiography of the cervical carotid artery were performed bilaterally in 15 patients with suspected stenoses. A new semi-automatic segmentation and new rendering methods were used. The degree of stenosis of internal carotid arteries, as determined both by axial slices and 3D images (surface, integral, maximum-intensity-projection, and raysum-rendered images), was compared qualitatively and quantitatively to angiographic findings. In correlation to angiography, the accuracy in determining the stenosis classification of internal carotid arteries was of 97% for axial slices and 59-90% for 3D images, respectively. Raysum (pseudoradiograph) rendering was found to be the most reliable rendering method and gave the most similar results to angiography. The accuracy of all rendering methods was improved by applying calcification removing algorithm, with a statistically significant difference between surface rendering without plaque removal and raysum rendering using the removing algorithm. (orig.)

  7. H(+) -pyrophosphatase from Salicornia europaea confers tolerance to simultaneously occurring salt stress and nitrogen deficiency in Arabidopsis and wheat.

    Science.gov (United States)

    Lv, Sulian; Jiang, Ping; Nie, Lingling; Chen, Xianyang; Tai, Fang; Wang, Duoliya; Fan, Pengxiang; Feng, Juanjuan; Bao, Hexigeduleng; Wang, Jinhui; Li, Yinxin

    2015-11-01

    High salinity and nitrogen (N) deficiency in soil are two key factors limiting crop productivity, and they usually occur simultaneously. Here we firstly found that H(+) -PPase is involved in salt-stimulated NO3 (-) uptake in the euhalophyte Salicornia europaea. Then, two genes (named SeVP1 and SeVP2) encoding H(+) -PPase from S. europaea were characterized. The expression of SeVP1 and SeVP2 was induced by salt stress and N starvation. Both SeVP1 or SeVP2 transgenic Arabidopsis and wheat plants outperformed the wild types (WTs) when high salt and low N occur simultaneously. The transgenic Arabidopsis plants maintained higher K(+) /Na(+) ratio in leaves and exhibited increased NO3 (-) uptake, inorganic pyrophosphate-dependent vacuolar nitrate efflux and assimilation capacity under this double stresses. Furthermore, they had more soluble sugars in shoots and roots and less starch accumulation in shoots than WT. These performances can be explained by the up-regulated expression of ion, nitrate and sugar transporter genes in transgenic plants. Taken together, our results suggest that up-regulation of H(+) -PPase favours the transport of photosynthates to root, which could promote root growth and integrate N and carbon metabolism in plant. This work provides potential strategies for improving crop yields challenged by increasing soil salinization and shrinking farmland. PMID:25920512

  8. Constitutive activation of AtMEK5, a MAPK kinase, induces salicylic acid-independent cell death in Arabidopsis thaliana

    Institute of Scientific and Technical Information of China (English)

    LIU Hongxia; WANG Ying; ZHOU Tianhong; SUN Yujing; LIU Guoqin; REN Dongtao

    2004-01-01

    AtMEK5DD is an active mutant of AtMEK5, a MAP kinase kinase in Arabidopsis. Induction of AtMEK5DD expression in transgenic plants leads to activation of 44 and 48 kD MAPKs and causes a rapid cell death. To compare the cell death induced by the expression of AtMEK5DD with the HR-cell death induced by avirulence pathogen infection, we analyzed the activation of downstream MAP Kinase and induction of PR genes expression in permanent transgenic Arabidopsis plants. In-gel kinase activity assay revealed that the infection of Pseudomonas syringae DC3000 harboring Avr Rpt2 gene also lead to activation of 44 and 48 kD MAPKs. PAL, PR1 and PR5 were strongly induced in plants undergoing HR-cell death caused by the infection of P. Syringae DC3000, while only the expression of PR5 was strongly induced in transgenic plants expressing AtMEK5DD protein. NahG protein in AtMEK5DD×NahG plants cannot suppress the cell death induced by AtMEK5DD. And AtMEK5DD protein expressed AtMEK5DD×NahG plants showed no significant change in salicylic acid (SA)level.All these suggest that the cell death induced by the activation of AtMEK5 is salicylic acid-independent.

  9. Ectopic expression of soybean GmKNT1 in Arabidopsis results in altered leaf morphology and flower identity

    Institute of Scientific and Technical Information of China (English)

    Jun Liu; Da Ha; Zongming Xie; Chunmei Wang; Huiwen Wang; Wanke Zhang; Jinsong Zhang; Shouyi Chen

    2008-01-01

    Plant morphology is specified by leaves and flowers, and the shoot apical meristem (SAM) defines the architecture of plant leaves and flowers. Here, we reported the characterization of a soybean KNOX gene GmKNT1, which was highly homologous to Arabidopsis STM. The GmKNT1 was strongly expressed in roots, flowers and developing seeds. Its expression could be induced by IAA, ABA and JA, but inhibited by GA or cytokinin. Staining of the transgenic plants overexpressing GmKNT1-GUS fusion protein revealed that the GmKNT1 was mainly expressed at lobe region, SAM of young leaves, sepal and carpel, not in seed and mature leaves. Scanning electron micros- copy (SEM) disclosed multiple changes in morphology of the epidermal cells and stigma. The transgenic Arabidopsis plants overexpress- ing the GmKNT1 showed small and lobed leaves, shortened internodes and small clustered inflorescence. The lobed leaves might result from the function of the meristems located at the boundary of the leaf. Compared with wild type plants, transgenic plants had higher ex- pression of the SAM-related genes including the CUP, WUS, CUC1, KNAT2 and KNAT6. These results indicated that the GmKNT1 could affect multiple aspects of plant growth and development by regulation of downstream genes expression.

  10. Expression of aberrant forms of AUXIN RESPONSE FACTOR8 stimulates parthenocarpy in Arabidopsis and tomato.

    Science.gov (United States)

    Goetz, Marc; Hooper, Lauren C; Johnson, Susan D; Rodrigues, Julio Carlyle Macedo; Vivian-Smith, Adam; Koltunow, Anna M

    2007-10-01

    Fruit initiation in Arabidopsis (Arabidopsis thaliana) is generally repressed until fertilization occurs. However, mutations in AUXIN RESPONSE FACTOR8 (ARF8) uncouple fruit initiation from fertilization, resulting in the formation of seedless, parthenocarpic fruit. Here we induced parthenocarpy in wild-type Arabidopsis by introducing either the mutant genomic (g) Atarf8-4 sequence or gAtARF8:beta-glucuronidase translational fusion constructs by plant transformation. Silencing of endogenous AtARF8 transcription was not observed, indicating that the introduced, aberrant ARF8 transcripts were compromising the function of endogenous ARF8 and/or associated factors involved in suppressing fruit initiation. To analyze the role of ARF8 in tomato (Solanum lycopersicum) we initially emasculated 23 tomato cultivars to test for background parthenocarpy. Surprisingly, all had a predisposition to initiate fertilization-independent fruit growth. Expression of gAtarf8-4 in transgenic tomato ('Monalbo') resulted in a significant increase in the number and size of parthenocarpic fruit. Isolation of tomato ARF8 cDNA indicated significant sequence conservation with AtARF8. SlARF8 may therefore control tomato fruit initiation in a similar manner as AtARF8 does in Arabidopsis. Two SlARF8 cDNAs differing in size by 5 bp were found, both arising from the same gene. The smaller cDNA is a splice variant and is also present in Arabidopsis. We propose that low endogenous levels of the splice variant products might interfere with efficient formation/function of a complex repressing fruit initiation, thereby providing an explanation for the observed ovary expansion in tomato and also Arabidopsis after emasculation. Increasing the levels of aberrant Atarf8-4 transcripts may further destabilize formation/function of the complex in a dosage-dependent manner enhancing tomato parthenocarpic fruit initiation frequency and size and mimicking the parthenocarpic dehiscent silique phenotype found in

  11. Arabidopsis thaliana—Aphid Interaction

    OpenAIRE

    Louis, Joe; Singh, Vijay,; Shah, Jyoti

    2012-01-01

    Aphids are important pests of plants that use their stylets to tap into the sieve elements to consume phloem sap. Besides the removal of photosynthates, aphid infestation also alters source-sink patterns. Most aphids also vector viral diseases. In this chapter, we will summarize on recent significant findings in plant-aphid interaction, and how studies involving Arabidopsis thaliana and Myzus persicae (Sülzer), more commonly known as the green peach aphid (GPA), are beginning to provide impor...

  12. Selenium Speciation in Arabidopsis Thaliana

    OpenAIRE

    Wang, Xiaoou

    2011-01-01

    Selenium has been proved as an essential micronutrient and is beneficial to animals and humans. It is a structural component of the important antioxidant enzyme, glutathione peroxidase, which catalyzes reactions to detoxify reactive oxygen species. However, the essentiality of Se in plants remains controversial and the protective role of Se in plants has rarely been investigated. In this study, Arabidopsis thaliana was grown in controlled environments having selenate or selenite enriched medi...

  13. Stem cell organization in Arabidopsis

    OpenAIRE

    Wendrich, J.R.

    2016-01-01

    Growth of plant tissues and organs depends on continuous production of new cells, by niches of stem cells. Stem cells typically divide to give rise to one differentiating daughter and one non-differentiating daughter. This constant process of self-renewal ensures that the niches of stem cells or meristems stay active throughout plant-life. Specification of stem cells occurs very early during development of the emrbyo and they are maintained during later stages. The Arabidopsis embryo is a hig...

  14. Immunomodulation by the Pseudomonas syringae HopZ type III effector family in Arabidopsis.

    Directory of Open Access Journals (Sweden)

    Jennifer D Lewis

    Full Text Available Pseudomonas syringae employs a type III secretion system to inject 20-30 different type III effector (T3SE proteins into plant host cells. A major role of T3SEs is to suppress plant immune responses and promote bacterial infection. The YopJ/HopZ acetyltransferases are a superfamily of T3SEs found in both plant and animal pathogenic bacteria. In P. syringae, this superfamily includes the evolutionarily diverse HopZ1, HopZ2 and HopZ3 alleles. To investigate the roles of the HopZ family in immunomodulation, we generated dexamethasone-inducible T3SE transgenic lines of Arabidopsis for HopZ family members and characterized them for immune suppression phenotypes. We show that all of the HopZ family members can actively suppress various facets of Arabidopsis immunity in a catalytic residue-dependent manner. HopZ family members can differentially suppress the activation of mitogen-activated protein (MAP kinase cascades or the production of reactive oxygen species, whereas all members can promote the growth of non-virulent P. syringae. Localization studies show that four of the HopZ family members containing predicted myristoylation sites are localized to the vicinity of the plasma membrane while HopZ3 which lacks the myristoylation site is at least partially nuclear localized, suggesting diversification of immunosuppressive mechanisms. Overall, we demonstrate that despite significant evolutionary diversification, all HopZ family members can suppress immunity in Arabidopsis.

  15. Overexpression of Late Embryogenesis Abundant 14 enhances Arabidopsis salt stress tolerance.

    Science.gov (United States)

    Jia, Fengjuan; Qi, Shengdong; Li, Hui; Liu, Pu; Li, Pengcheng; Wu, Changai; Zheng, Chengchao; Huang, Jinguang

    2014-11-28

    Late embryogenesis abundant (LEA) proteins are implicated in various abiotic stresses in higher plants. In this study, we identified a LEA protein from Arabidopsis thaliana, AtLEA14, which was ubiquitously expressed in different tissues and remarkably induced with increased duration of salt treatment. Subcellular distribution analysis demonstrated that AtLEA14 was mainly localized in the cytoplasm. Transgenic Arabidopsis and yeast overexpressing AtLEA14 all exhibited enhanced tolerance to high salinity. The transcripts of salt stress-responsive marker genes (COR15a, KIN1, RD29B and ERD10) were overactivated in AtLEA14 overexpressing lines compared with those in wild type plants under normal or salt stress conditions. In vivo and in vitro analysis showed that AtLEA14 could effectively stabilize AtPP2-B11, an important E3 ligase. These results suggested that AtLEA14 had important protective functions under salt stress conditions in Arabidopsis. PMID:25450686

  16. Isolation and Functional Analysis of ZmLTP3, a Homologue to Arabidopsis LTP3

    Directory of Open Access Journals (Sweden)

    Guo-Hui Ma

    2013-03-01

    Full Text Available Plant lipid transfer proteins (LTPs are encoded by multigene families and play important roles in plant physiology. One full-length cDNA encoding an Arabidopsis LTP3 homologue was isolated from maize by RT-PCR and named as ZmLTP3. RT-PCR analysis indicated that the ZmLTP3 expression is induced by salicylic acid (SA, mannitol and salt. Furthermore, in different tissues the ZmLTP3 displayed different expression patterns, indicating that ZmLTP3 may play multiple roles in stress resistance. Over-expression of ZmLTP3 in wild-type Arabidopsis resulted in the increased salt tolerance. Under salt stress condition, compared to wild-type (WT plants, transgenic Arabidopsis grew better, had higher seedling fresh (FW, dry weight (DW, seed yields, proline content and lower MDA content and relative electric conductivity level. Our results suggest that maize ZmLTP3 might encode a member of LTPs family and play roles in salt resistance.

  17. Isolation and Functional Analysis of ZmLTP3, a Homologue to Arabidopsis LTP3.

    Science.gov (United States)

    Zou, Hua-Wen; Tian, Xiao-Hai; Ma, Guo-Hui; Li, Zhi-Xin

    2013-01-01

    Plant lipid transfer proteins (LTPs) are encoded by multigene families and play important roles in plant physiology. One full-length cDNA encoding an Arabidopsis LTP3 homologue was isolated from maize by RT-PCR and named as ZmLTP3. RT-PCR analysis indicated that the ZmLTP3 expression is induced by salicylic acid (SA), mannitol and salt. Furthermore, in different tissues the ZmLTP3 displayed different expression patterns, indicating that ZmLTP3 may play multiple roles in stress resistance. Over-expression of ZmLTP3 in wild-type Arabidopsis resulted in the increased salt tolerance. Under salt stress condition, compared to wild-type (WT) plants, transgenic Arabidopsis grew better, had higher seedling fresh (FW), dry weight (DW), seed yields, proline content and lower MDA content and relative electric conductivity level. Our results suggest that maize ZmLTP3 might encode a member of LTPs family and play roles in salt resistance. PMID:23455470

  18. Expression of human ARGONAUTE 2 inhibits endogenous microRNA activity in Arabidopsis

    Directory of Open Access Journals (Sweden)

    Ira eDeveson

    2013-04-01

    Full Text Available Plant and animal microRNA (miRNA pathways share many analogous components, the ARGONAUTE (AGO proteins being foremost among them. We sought to ascertain the degree of functional conservation shared by Homo sapiens ARGONAUTE 2 (HsAGO2 and Arabidopsis thaliana ARGONAUTE 1 (AtAGO1, which are the predominant AGO family members involved with miRNA activity in their respective species. Transgenic Arabidopsis plants expressing HsAGO2 were indistinguishable from counterparts over-expressing AtAGO1, each group exhibiting the morphological and molecular hallmarks of miRNA-pathway loss-of-function alleles. However, unlike AtAGO1, HsAGO2 was unable to rescue the ago1-27 allele. We conclude that, despite the evolutionary gulf between them, HsAGO2 is likely capable of interacting with some component/s of the Arabidopsis miRNA pathway, thereby perturbing its operation, although differences have arisen such that HsAGO2 alone is insufficient to confer efficient silencing of miRNA targets in planta.

  19. Target of Rapamycin Is a Key Player for Auxin Signaling Transduction in Arabidopsis.

    Science.gov (United States)

    Deng, Kexuan; Yu, Lihua; Zheng, Xianzhe; Zhang, Kang; Wang, Wanjing; Dong, Pan; Zhang, Jiankui; Ren, Maozhi

    2016-01-01

    Target of rapamycin (TOR), a master sensor for growth factors and nutrition availability in eukaryotic species, is a specific target protein of rapamycin. Rapamycin inhibits TOR kinase activity viaFK506 binding protein 12 kDa (FKBP12) in all examined heterotrophic eukaryotic organisms. In Arabidopsis, several independent studies have shown that AtFKBP12 is non-functional under aerobic condition, but one study suggests that AtFKBP12 is functional during anaerobic growth. However, the functions of AtFKBP12 have never been examined in parallel under aerobic and anaerobic growth conditions so far. To this end, we cloned the FKBP12 gene of humans, yeast, and Arabidopsis, respectively. Transgenic plants were generated, and pharmacological examinations were performed in parallel with Arabidopsis under aerobic and anaerobic conditions. ScFKBP12 conferred plants with the strongest sensitivity to rapamycin, followed by HsFKBP12, whereas AtFKBP12 failed to generate rapamycin sensitivity under aerobic condition. Upon submergence, yeast and human FKBP12 can significantly block cotyledon greening while Arabidopsis FKBP12 only retards plant growth in the presence of rapamycin, suggesting that hypoxia stress could partially restore the functions of AtFKBP12 to bridge the interaction between rapamycin and TOR. To further determine if communication between TOR and auxin signaling exists in plants, yeast FKBP12 was introduced into DR5::GUS homozygous plants. The transgenic plants DR5/BP12 were then treated with rapamycin or KU63794 (a new inhibitor of TOR). GUS staining showed that the auxin content of root tips decreased compared to the control. DR5/BP12 plants lost sensitivity to auxin after treatment with rapamycin. Auxin-defective phenotypes, including short primary roots, fewer lateral roots, and loss of gravitropism, occurred in DR5/BP12 plants when seedlings were treated with rapamycin+KU63794. This indicated that the combination of rapamycin and KU63794 can significantly

  20. The bZIP Protein VIP1 Is Involved in Touch Responses in Arabidopsis Roots.

    Science.gov (United States)

    Tsugama, Daisuke; Liu, Shenkui; Takano, Tetsuo

    2016-06-01

    VIP1 is a bZIP transcription factor in Arabidopsis (Arabidopsis thaliana). VIP1 transiently accumulates in the nucleus when cells are exposed to hypoosmotic conditions, but its physiological relevance is unclear. This is possibly because Arabidopsis has approximately 10 close homologs of VIP1 and they function redundantly. To examine their physiological roles, transgenic plants overexpressing a repression domain-fused form of VIP1 (VIP1-SRDXox plants), in which the gene activation mediated by VIP1 is expected to be repressed, were generated. Because hypoosmotic stress can mimic mechanical stimuli (e.g. touch), the touch-induced root-waving phenotypes and gene expression patterns in those transgenic plants were examined. VIP1-SRDXox plants exhibited more severe root waving and lower expression of putative VIP1 target genes. The expression of the VIP1-green fluorescent protein (GFP) fusion protein partially suppressed the VIP1-SRDX-induced increase in root waving when expressed in the VIP1-SRDXox plants. These results suggest that VIP1 can suppress the touch-induced root waving. The VIP1-SRDX-induced increase in root waving was also suppressed when the synthetic auxin 2,4-dichlorophenoxy acetic acid or the ethylene precursor 1-aminocyclopropane-1-carboxylic acid, which is known to activate auxin biosynthesis, was present in the growth medium. Root cap cells with the auxin marker DR5rev::GFP were more abundant in the VIP1-SRDXox background than in the wild-type background. Auxin is transported via the root cap, and the conditions of outermost root cap layers were abnormal in VIP1-SRDXox plants. These results raise the possibility that VIP1 influences structures of the root cap and thereby regulates the local auxin responses in roots. PMID:27208231

  1. Overexpression of rice black-streaked dwarf virus p7-1 in Arabidopsis results in male sterility due to non-dehiscent anthers.

    Directory of Open Access Journals (Sweden)

    Feng Sun

    Full Text Available Rice black-streaked dwarf virus (RBSDV, a member of the genus Fijivirus in the family Reoviridae, is propagatively transmitted by the small brown planthopper (Laodelphax striatellus Fallén. RBSDV causes rice black-streaked dwarf and maize rough dwarf diseases, which lead to severe yield losses in crops in China. Although several RBSDV proteins have been studied in detail, the functions of the nonstructural protein P7-1 are still largely unknown. To investigate the role of the P7-1 protein in virus pathogenicity, transgenic Arabidopsis thaliana plants were generated in which the P7-1 gene was expressed under the control of the 35S promoter. The RBSDV P7-1-transgenic Arabidopsis plants (named P7-1-OE were male sterility. Flowers and pollen from P7-1-transgenic plants were of normal size and shape, and anthers developed to the normal size but failed to dehisce. The non-dehiscent anthers observed in P7-1-OE were attributed to decreased lignin content in the anthers. Furthermore, the reactive oxygen species levels were quite low in the transgenic plants compared with the wild type. These results indicate that ectopic expression of the RBSDV P7-1 protein in A. thaliana causes male sterility, possibly through the disruption of the lignin biosynthesis and H2O2-dependent polymerization pathways.

  2. Transgenerational stress memory is not a general response in Arabidopsis.

    Directory of Open Access Journals (Sweden)

    Ales Pecinka

    Full Text Available Adverse conditions can trigger DNA damage as well as DNA repair responses in plants. A variety of stress factors are known to stimulate homologous recombination, the most accurate repair pathway, by increasing the concentration of necessary enzymatic components and the frequency of events. This effect has been reported to last into subsequent generations not exposed to the stress. To establish a basis for a genetic analysis of this transgenerational stress memory, a broad range of treatments was tested for quantitative effects on homologous recombination in the progeny. Several Arabidopsis lines, transgenic for well-established recombination traps, were exposed to 10 different physical and chemical stress treatments, and scored for the number of somatic homologous recombination (SHR events in the treated generation as well as in the two subsequent generations that were not treated. These numbers were related to the expression level of genes involved in homologous recombination and repair. SHR was enhanced after the majority of treatments, confirming previous data and adding new effective stress types, especially interference with chromatin. Compounds that directly modify DNA stimulated SHR to values exceeding previously described induction rates, concomitant with an induction of genes involved in SHR. In spite of the significant stimulation in the stressed generations, the two subsequent non-treated generations only showed a low and stochastic increase in SHR that did not correlate with the degree of stimulation in the parental plants. Transcripts coding for SHR enzymes generally returned to pre-treatment levels in the progeny. Thus, transgenerational effects on SHR frequency are not a general response to abiotic stress in Arabidopsis and may require special conditions.

  3. An International Bioinformatics Infrastructure to Underpin the Arabidopsis Community

    Science.gov (United States)

    The future bioinformatics needs of the Arabidopsis community as well as those of other scientific communities that depend on Arabidopsis resources were discussed at a pair of recent meetings held by the Multinational Arabidopsis Steering Committee (MASC) and the North American Arabidopsis Steering C...

  4. Whole transcriptome analysis of transgenic barley with altered cytokinin homeostasis and increased tolerance to drought stress.

    Science.gov (United States)

    Vojta, Petr; Kokáš, Filip; Husičková, Alexandra; Grúz, Jiří; Bergougnoux, Veronique; Marchetti, Cintia F; Jiskrová, Eva; Ježilová, Eliška; Mik, Václav; Ikeda, Yoshihisa; Galuszka, Petr

    2016-09-25

    Cytokinin plant hormones have been shown to play an important role in plant response to abiotic stresses. Herein, we expand upon the findings of Pospíšilová et al. [30] regarding preparation of novel transgenic barley lines overexpressing cytokinin dehydrogenase 1 gene from Arabidopsis under the control of mild root-specific promotor of maize β-glycosidase. These lines showed drought-tolerant phenotype mainly due to alteration of root architecture and stronger lignification of root tissue. A detailed transcriptomic analysis of roots of transgenic plants subjected to revitalization after drought stress revealed attenuated response through the HvHK3 cytokinin receptor and up-regulation of two transcription factors implicated in stress responses and abscisic acid sensitivity. Increased expression of several genes involved in the phenylpropanoid pathway as well as of genes encoding arogenate dehydratase/lyase participating in phenylalanine synthesis was found in roots during revitalization. Although more precursors of lignin synthesis were present in roots after drought stress, final lignin accumulation did not change compared to that in plants grown under optimal conditions. Changes in transcriptome indicated a higher auxin turnover in transgenic roots. The same analysis in leaves revealed that genes encoding putative enzymes responsible for production of jasmonates and other volatile compounds were up-regulated. Although transgenic barley leaves showed lower chlorophyll content and down-regulation of genes encoding proteins involved in photosynthesis than did wild-type plants when cultivated under optimal conditions, they did show a tendency to return to initial photochemical activities faster than did wild-type leaves when re-watered after severe drought stress. In contrast to optimal conditions, comparative transcriptomic analysis of revitalized leaves displayed up-regulation of genes encoding enzymes and proteins involved in photosynthesis, and especially

  5. Generation of transgenic Hydra by embryo microinjection.

    Science.gov (United States)

    Juliano, Celina E; Lin, Haifan; Steele, Robert E

    2014-01-01

    As a member of the phylum Cnidaria, the sister group to all bilaterians, Hydra can shed light on fundamental biological processes shared among multicellular animals. Hydra is used as a model for the study of regeneration, pattern formation, and stem cells. However, research efforts have been hampered by lack of a reliable method for gene perturbations to study molecular function. The development of transgenic methods has revitalized the study of Hydra biology(1). Transgenic Hydra allow for the tracking of live cells, sorting to yield pure cell populations for biochemical analysis, manipulation of gene function by knockdown and over-expression, and analysis of promoter function. Plasmid DNA injected into early stage embryos randomly integrates into the genome early in development. This results in hatchlings that express transgenes in patches of tissue in one or more of the three lineages (ectodermal epithelial, endodermal epithelial, or interstitial). The success rate of obtaining a hatchling with transgenic tissue is between 10% and 20%. Asexual propagation of the transgenic hatchling is used to establish a uniformly transgenic line in a particular lineage. Generating transgenic Hydra is surprisingly simple and robust, and here we describe a protocol that can be easily implemented at low cost. PMID:25285460

  6. Arabidopsis CDS blastp result: AK106750 [KOME

    Lifescience Database Archive (English)

    Full Text Available AK106750 002-115-C09 At4g15560.1 1-deoxy-D-xylulose 5-phosphate synthase, putative / 1-deoxyxylu ... phate synthase, putative / DXP-synthase, putative (DEF ) (CLA1) identical to SP|Q38854 Probable 1-deoxy-D- ... (DXPS). [Mouse-ear cress] {Arabidopsis thaliana}, DEF ... (def icient in photosynthesis) protein [Arabidopsis ...

  7. Arabidopsis CDS blastp result: AK104851 [KOME

    Lifescience Database Archive (English)

    Full Text Available AK104851 001-043-A10 At4g15560.1 1-deoxy-D-xylulose 5-phosphate synthase, putative / 1-deoxyxylu ... phate synthase, putative / DXP-synthase, putative (DEF ) (CLA1) identical to SP|Q38854 Probable 1-deoxy-D- ... (DXPS). [Mouse-ear cress] {Arabidopsis thaliana}, DEF ... (def icient in photosynthesis) protein [Arabidopsis ...

  8. Arabidopsis CDS blastp result: AK100909 [KOME

    Lifescience Database Archive (English)

    Full Text Available AK100909 J023132G24 At4g15560.1 1-deoxy-D-xylulose 5-phosphate synthase, putative / 1-deoxyxylul ... phate synthase, putative / DXP-synthase, putative (DEF ) (CLA1) identical to SP|Q38854 Probable 1-deoxy-D- ... (DXPS). [Mouse-ear cress] {Arabidopsis thaliana}, DEF ... (def icient in photosynthesis) protein [Arabidopsis ...

  9. Arabidopsis CDS blastp result: AK058950 [KOME

    Lifescience Database Archive (English)

    Full Text Available AK058950 001-020-A07 At4g15560.1 1-deoxy-D-xylulose 5-phosphate synthase, putative / 1-deoxyxylu ... phate synthase, putative / DXP-synthase, putative (DEF ) (CLA1) identical to SP|Q38854 Probable 1-deoxy-D- ... (DXPS). [Mouse-ear cress] {Arabidopsis thaliana}, DEF ... (def icient in photosynthesis) protein [Arabidopsis ...

  10. Arabidopsis CDS blastp result: AK059821 [KOME

    Lifescience Database Archive (English)

    Full Text Available AK059821 006-205-D11 At4g15560.1 1-deoxy-D-xylulose 5-phosphate synthase, putative / 1-deoxyxylu ... phate synthase, putative / DXP-synthase, putative (DEF ) (CLA1) identical to SP|Q38854 Probable 1-deoxy-D- ... (DXPS). [Mouse-ear cress] {Arabidopsis thaliana}, DEF ... (def icient in photosynthesis) protein [Arabidopsis ...

  11. Arabidopsis CDS blastp result: AK064944 [KOME

    Lifescience Database Archive (English)

    Full Text Available AK064944 J013000P14 At4g15560.1 1-deoxy-D-xylulose 5-phosphate synthase, putative / 1-deoxyxylul ... phate synthase, putative / DXP-synthase, putative (DEF ) (CLA1) identical to SP|Q38854 Probable 1-deoxy-D- ... (DXPS). [Mouse-ear cress] {Arabidopsis thaliana}, DEF ... (def icient in photosynthesis) protein [Arabidopsis ...

  12. Arabidopsis CDS blastp result: AK068400 [KOME

    Lifescience Database Archive (English)

    Full Text Available AK068400 J013151M04 At3g45810.1 ferric reductase-like transmembrane component family protein sim ... ilar to respiratory burst ... oxidase protein D RbohD from Arabidopsis thaliana, ... EMBL:AF055357 [gi:3242789], similar to respiratory burst ... oxidase protein D RbohD from Arabidopsis thaliana, ...

  13. Arabidopsis CDS blastp result: AK066013 [KOME

    Lifescience Database Archive (English)

    Full Text Available AK066013 J013047I12 At3g45810.1 ferric reductase-like transmembrane component family protein sim ... ilar to respiratory burst ... oxidase protein D RbohD from Arabidopsis thaliana, ... EMBL:AF055357 [gi:3242789], similar to respiratory burst ... oxidase protein D RbohD from Arabidopsis thaliana, ...

  14. Arabidopsis CDS blastp result: AK100241 [KOME

    Lifescience Database Archive (English)

    Full Text Available AK100241 J023054P13 At3g45810.1 ferric reductase-like transmembrane component family protein sim ... ilar to respiratory burst ... oxidase protein D RbohD from Arabidopsis thaliana, ... EMBL:AF055357 [gi:3242789], similar to respiratory burst ... oxidase protein D RbohD from Arabidopsis thaliana, ...

  15. Arabidopsis CDS blastp result: AK318553 [KOME

    Lifescience Database Archive (English)

    Full Text Available AK318553 J075145A22 At3g45810.1 68416.m04958 ferric reductase-like transmembrane component famil ... y protein similar to respiratory burst ... oxidase protein D RbohD from Arabidopsis thaliana, ... EMBL:AF055357 [gi:3242789], similar to respiratory burst ... oxidase protein D RbohD from Arabidopsis thaliana, ...

  16. Using "Arabidopsis" Genetic Sequences to Teach Bioinformatics

    Science.gov (United States)

    Zhang, Xiaorong

    2009-01-01

    This article describes a new approach to teaching bioinformatics using "Arabidopsis" genetic sequences. Several open-ended and inquiry-based laboratory exercises have been designed to help students grasp key concepts and gain practical skills in bioinformatics, using "Arabidopsis" leucine-rich repeat receptor-like kinase (LRR RLK) genetic…

  17. 3D Plant Cell Architecture of Arabidopsis thaliana (Brassicaceae Using Focused Ion Beam–Scanning Electron Microscopy

    Directory of Open Access Journals (Sweden)

    Bhawana

    2014-06-01

    Full Text Available Premise of the study: Focused ion beam–scanning electron microscopy (FIB-SEM combines the ability to sequentially mill the sample surface and obtain SEM images that can be used to create 3D renderings with micron-level resolution. We have applied FIB-SEM to study Arabidopsis cell architecture. The goal was to determine the efficacy of this technique in plant tissue and cellular studies and to demonstrate its usefulness in studying cell and organelle architecture and distribution. Methods: Seed aleurone, leaf mesophyll, stem cortex, root cortex, and petal lamina from Arabidopsis were fixed and embedded for electron microscopy using protocols developed for animal tissues and modified for use with plant cells. Each sample was sectioned using the FIB and imaged with SEM. These serial images were assembled to produce 3D renderings of each cell type. Results: Organelles such as nuclei and chloroplasts were easily identifiable, and other structures such as endoplasmic reticula, lipid bodies, and starch grains were distinguishable in each tissue. Discussion: The application of FIB-SEM produced 3D renderings of five plant cell types and offered unique views of their shapes and internal content. These results demonstrate the usefulness of FIB-SEM for organelle distribution and cell architecture studies.

  18. Moisture Transfer through Facades Covered with Organic Binder Renders

    Directory of Open Access Journals (Sweden)

    Carmen DICO

    2013-07-01

    Full Text Available Year after year we witness the negative effect of water over buildings, caused by direct or indirect actions. This situation is obvious in case of old, historical building, subjected to this aggression for a long period of time, but new buildings are also affected. Moisture in building materials causes not only structural damage, but also reduces the thermal insulation capacity of building components.Materials like plasters or paints have been used historically for a long period of time, fulfilling two basics functions: Decoration and Protection. The most acute demands are made on exterior plasters, as they, besides being an important decorative element for the facade, must perform two different functions simultaneously: protect the substrate against weathering and moisture without sealing, providing it a certain ability to “breathe” (Heilen, 2005. In order to accomplish this aim, the first step is to understand the hygrothermal behavior of coating and substrate and define the fundamental principles of moisture transfer; According to Künzel’s Facade Protection Theory, two material properties play the most important role: Water absorption and Vapor permeability.In the context of recently adoption (2009 of the “harmonized” European standard EN 15824 – „Specifications for external renders and internal plasters based on organic binders”, this paper deals extensively with the interaction of the two mentioned above properties for the coating materials, covered by EN 15824.

  19. Differentiation renders susceptibility to excitotoxicity in HT22 neurons

    Institute of Scientific and Technical Information of China (English)

    Minchao He; Jun Liu; Shaowu Cheng; Yigang Xing; William Z Suo

    2013-01-01

    HT22 is an immortalized mouse hippocampal neuronal cell line that does not express cholinergic and glutamate receptors like mature hippocampal neurons in vivo. This in part prevents its use as a model for mature hippocampal neurons in memory-related studies. We now report that HT22 cells were appropriately induced to differentiate and possess properties similar to those of mature hippocampal neurons in vivo, such as becoming more glutamate-receptive and excitatory. Results showed that sensitivity of HT22 cells to glutamate-induced toxicity changed dramatically when comparing undifferentiated with differentiated cells, with the half-effective concentration for differentiated cells reducing approximately two orders of magnitude. Moreover, glutamate-induced toxicity in differentiated cells, but not undifferentiated cells, was inhibited by the N-methyl-D- aspartate receptor antagonists MK-801 and memantine. Evidently, differentiated HT22 cells expressed N-methyl-D-aspartate receptors, while undifferentiated cells did not. Our experimental findings indicated that differentiation is important for immortalized cell lines to render post-mitotic neuronal properties, and that differentiated HT22 neurons represent a better model of hippocampal neurons than undifferentiated cells.

  20. Rendering log aesthetic curves via Runge-Kutta method

    Science.gov (United States)

    Gobithaasan, R. U.; Meng, T. Y.; Piah, A. R. M.; Miura, K. T.

    2014-07-01

    Log Aesthetic Curves (LAC) are visually pleasing curves which has been developed using monotonic curvature profile. Hence, it can be easily implemented in product design environment, e.g, Rhino 3D CAD systems. LAC is generally represented in an integral form of its turning angle. Traditionally, Gaussian-Kronrod method has been used to render this curve which consumes less than one second for a given interval. Recently, Incomplete Gamma Function was proposed to represent LAC analytically which decreases the computation time up to 13 times. However, only certain value of shape parameters (denoted as α) which dictates the types of curves generated for LAC, can be used to compute LAC. In this paper, the classical Runge-Kutta (RK4) method is proposed to evaluate LAC numerically to reduce the LAC computation time for arbitrary, α. The preliminary result looks promising where the evaluation time is decreased tremendously. This paper also demonstrates the accuracy control of LAC by reducing the stepsize of RK4. The computation time and the accuracy for various α, are also illustrated in the last section of this paper.

  1. Changing the color of textiles with realistic visual rendering

    Science.gov (United States)

    Hébert, Mathieu; Henckens, Lambert; Barbier, Justine; Leboulleux, Lucie; Page, Marine; Roujas, Lucie; Cazier, Anthony

    2015-03-01

    Fast and easy preview of a fabric without having to produce samples would be very profitable for textile designers, but remains a technological challenge. As a first step towards this objective, we study the possibility of making images of a real sample, and changing virtually the colors of its yarns while preserving the shine and shadow texture. We consider two types of fabrics: Jacquard weave fabrics made of polyester warp and weft yarns of different colors, and satin ribbons made of polyester and metallic yarns. For the Jacquard fabric, we make a color picture with a scanner on a sample in which the yarns have contrasted colors, threshold this image in order to distinguish the pixels corresponding to each yarn, and accordingly modify their hue and chroma values. This method is simple to operate but do not enable to simulate the angle-dependent shine. A second method, tested on the satin ribbon made of black polyester and achromatic metallic yarns, is based on polarized imaging. We analyze the polarization state of the reflected light which is different for dielectric and metallic materials illuminated by polarized light. We then add a fixed color value to the pixels representing the polyester yarns and modify the hue and chroma of the pixels representing the metallic yarns. This was performed for many incident angles of light, in order to render the twinkling effect displayed by these ribbons. We could verify through a few samples that the simulated previews reproduce real pictures with visually acceptable accuracy.

  2. Usefulness of volume rendering stereo-movie in neurosurgical craniotomies

    International Nuclear Information System (INIS)

    In recent years, the advancements in MR technology combined with the development of the multi-channel coil have resulted in substantially shortened inspection times. In addition, rapid improvement in functional performance in the workstation has produced a more simplified imaging-making process. Consequently, graphical images of intra-cranial lesions can be easily created. For example, the use of three-dimensional spoiled gradient echo (3D-SPGR) volume rendering (VR) after injection of a contrast medium is applied clinically as a preoperative reference image. Recently, improvements in 3D-SPGR VR high-resolution have enabled accurate surface images of the brain to be obtained. We used stereo-imaging created by weighted maximum intensity projection (Weighted MIP) to determine the skin incision line. Furthermore, the stereo imaging technique utilizing 3D-SPGR VR was actually used in cases presented here. The techniques we report here seemed to be very useful in the pre-operative simulation of neurosurgical craniotomy. (author)

  3. Grayscale performance enhancement for time-multiplexing light field rendering.

    Science.gov (United States)

    Su, Chen; Zhong, Qing; Peng, Yifan; Xu, Liang; Wang, Rui; Li, Haifeng; Liu, Xu

    2015-12-14

    One of the common approaches to compensate for the grayscale performance limitation in time-multiplexing light field displays is to employ a halftone technique. We propose an ordered-dithering halftone algorithm based on a 3-dimension super-mask to increase the gray levels of the time-multiplexing light field display. Our method makes full use of the overlapping perceived pixels which are caused by the time-multiplexing design, such that effectively trading-off the spatial resolution and color performance. A real-time rendering time-multiplexing display prototype is built to validate the proposed halftone algorithm. We conducted a user study to evaluate the quality of display scenes dithered by different super-mask configuration, which showed the consistency with the parameters we pre-calculated. The 3D ordered-dithering algorithm is able to present better visual perception than the conventional halftone algorithms with respect to grayscale representation, and flexible to be applied in different time-multiplexing light field display systems. PMID:26699051

  4. VITRAIL: Acquisition, Modeling, and Rendering of Stained Glass.

    Science.gov (United States)

    Thanikachalam, Niranjan; Baboulaz, Loic; Prandoni, Paolo; Trumpler, Stefan; Wolf, Sophie; Vetterli, Martin

    2016-10-01

    Stained glass windows are designed to reveal their powerful artistry under diverse and time-varying lighting conditions; virtual relighting of stained glass, therefore, represents an exceptional tool for the appreciation of this age old art form. However, as opposed to most other artifacts, stained glass windows are extremely difficult if not impossible to analyze using controlled illumination because of their size and position. In this paper, we present novel methods built upon image based priors to perform virtual relighting of stained glass artwork by acquiring the actual light transport properties of a given artifact. In a preprocessing step, we build a material-dependent dictionary for light transport by studying the scattering properties of glass samples in a laboratory setup. We can now use the dictionary to recover a light transport matrix in two ways: under controlled illuminations the dictionary constitutes a sparsifying basis for a compressive sensing acquisition, while in the case of uncontrolled illuminations the dictionary is used to perform sparse regularization. The proposed basis preserves volume impurities and we show that the retrieved light transport matrix is heterogeneous, as in the case of real world objects. We present the rendering results of several stained glass artifacts, including the Rose Window of the Cathedral of Lausanne, digitized using the presented methods. PMID:27416590

  5. Glyphostate-drift but not herbivory alters the rate of transgene flow from single and stacked trait transgenic canola (Brassica napus L.) to non-transgenic B. napus and B. rapa

    Science.gov (United States)

    While transgenic plants can offer agricultural benefits, the escape of transgenes out of crop fields is a major environmental concern. Escape of transgenic herbicide resistance has occurred between transgenic Brassica napus (canola) and weedy species in numerous locations. In t...

  6. Transgenic fish: present status and future directions.

    Science.gov (United States)

    Hew, C L

    1989-06-01

    Successful production of transgenic fish by gene transfer technology is a very important breakthrough in the techniques of genetic manipulation in animals. This will have an impact of an unprecedented scale in fish biology, aquaculture and mariculture. This is a summary of the workshop on the Transgenic Fish presented at this Symposium. The Workshop discussed the current knowledge, experimental difficulties and related topics of the transgenic fish. It recommended further research on better gene constructs, methods development, safety containment and the closer collaboration of researchers of different disciplines. PMID:24221801

  7. Expression of multiple proteins in transgenic plants

    Science.gov (United States)

    Vierstra, Richard D.; Walker, Joseph M.

    2002-01-01

    A method is disclosed for the production of multiple proteins in transgenic plants. A DNA construct for introduction into plants includes a provision to express a fusion protein of two proteins of interest joined by a linking domain including plant ubiquitin. When the fusion protein is produced in the cells of a transgenic plant transformed with the DNA construction, native enzymes present in plant cells cleave the fusion protein to release both proteins of interest into the cells of the transgenic plant. Since the proteins are produced from the same fusion protein, the initial quantities of the proteins in the cells of the plant are approximately equal.

  8. MicroRNA (miR396) negatively regulates expression of ceramidase-like genes in Arabidopsis

    Institute of Scientific and Technical Information of China (English)

    Dongmei Liu; Diqiu Yu

    2009-01-01

    MicroRNAs (miRNAs) are 21-23 nucleotide (nt), endogenous RNAs that regulate gene expression by targeting mRNAs for direct cleavage or translational repression in plants. In Arabidopsis, miR396 is encoded by two different loci (MIR396a and M1R396b) and sequence analysis suggests it may target three ceramidase-like genes (Atceramidase-like 1, Atceramidase-like 2 and Atceramidase-like 3). To demonstrate the biological function of miR396, we inserted the synthetic precursors, MIR396a or MIR396b, under the control of the enhanced cauliflower mosaic virus (CaMV) 35S promoter, into a plant transformation vector (pOCA30) and transformed the con-structs into Arabidopsis. The promoter increased miR396 levels by more than 2-fold, indicating appropriate maturation of the synthetic precursor MIR396a or MIR396b transcript in transgenic plants. Microarray analysis showed that the transcript levels of two ceramidase-like genes (Atceramidase-like 1, Atceramidase-like 2) were decreased by more than 2-fold and lactosylceramide 4-α-galactosyltransferase increased by more than 2-fold in transgenic plants compared with the empty vector-transformed plants. Northern blot analysis showed that the mRNA levels of the two ceramidase-like genes were significantly reduced in transgenic plants. These results indicated that miR396 probably plays a crucial role in the ceramide metabolism pathway by negatively regulating the expression of ceramidase-like genes in Arabidopsis.

  9. Insertion DNA Accelerates Meiotic Interchromosomal Recombination in Arabidopsis thaliana.

    Science.gov (United States)

    Sun, Xiao-Qin; Li, Ding-Hong; Xue, Jia-Yu; Yang, Si-Hai; Zhang, Yan-Mei; Li, Mi-Mi; Hang, Yue-Yu

    2016-08-01

    Nucleotide insertions/deletions are ubiquitous in eukaryotic genomes, and the resulting hemizygous (unpaired) DNA has significant, heritable effects on adjacent DNA. However, little is known about the genetic behavior of insertion DNA. Here, we describe a binary transgenic system to study the behavior of insertion DNA during meiosis. Transgenic Arabidopsis lines were generated to carry two different defective reporter genes on nonhomologous chromosomes, designated as "recipient" and "donor" lines. Double hemizygous plants (harboring unpaired DNA) were produced by crossing between the recipient and the donor, and double homozygous lines (harboring paired DNA) via self-pollination. The transfer of the donor's unmutated sequence to the recipient generated a functional β-glucuronidase gene, which could be visualized by histochemical staining and corroborated by polymerase chain reaction amplification and sequencing. More than 673 million seedlings were screened, and the results showed that meiotic ectopic recombination in the hemizygous lines occurred at a frequency  >6.49-fold higher than that in the homozygous lines. Gene conversion might have been exclusively or predominantly responsible for the gene correction events. The direct measurement of ectopic recombination events provided evidence that an insertion, in the absence of an allelic counterpart, could scan the entire genome for homologous counterparts with which to pair. Furthermore, the unpaired (hemizygous) architectures could accelerate ectopic recombination between itself and interchromosomal counterparts. We suggest that the ectopic recombination accelerated by hemizygous architectures may be a general mechanism for interchromosomal recombination through ubiquitously dispersed repeat sequences in plants, ultimately contributing to genetic renovation and eukaryotic evolution. PMID:27189569

  10. Overexpression of malate dehydrogenase in transgenic alfalfa enhances organic acid synthesis and confers tolerance to aluminum.

    Science.gov (United States)

    Tesfaye, M; Temple, S J; Allan, D L; Vance, C P; Samac, D A

    2001-12-01

    Al toxicity is a severe impediment to production of many crops in acid soil. Toxicity can be reduced through lime application to raise soil pH, however this amendment does not remedy subsoil acidity, and liming may not always be practical or cost-effective. Addition of organic acids to plant nutrient solutions alleviates phytotoxic Al effects, presumably by chelating Al and rendering it less toxic. In an effort to increase organic acid secretion and thereby enhance Al tolerance in alfalfa (Medicago sativa), we produced transgenic plants using nodule-enhanced forms of malate dehydrogenase and phosphoenolpyruvate carboxylase cDNAs under the control of the constitutive cauliflower mosaic virus 35S promoter. We report that a 1.6-fold increase in malate dehydrogenase enzyme specific activity in root tips of selected transgenic alfalfa led to a 4.2-fold increase in root concentration as well as a 7.1-fold increase in root exudation of citrate, oxalate, malate, succinate, and acetate compared with untransformed control alfalfa plants. Overexpression of phosphoenolpyruvate carboxylase enzyme specific activity in transgenic alfalfa did not result in increased root exudation of organic acids. The degree of Al tolerance by transformed plants in hydroponic solutions and in naturally acid soil corresponded with their patterns of organic acid exudation and supports the concept that enhancing organic acid synthesis in plants may be an effective strategy to cope with soil acidity and Al toxicity. PMID:11743127

  11. Efficient and Accurate Volume Rendering on Face-Centered and Body-Centered Cubic Grids

    OpenAIRE

    Smed, Karl-Oskar

    2015-01-01

    The body centered cubic grid (BCC) and face centered cubic grid (FCC) offer improved sampling properties when compared to the cartesian grid. Despite this there is little software and hardware support for volume rendering of data stored in one of these grids. This project is a continuation of a project adding support for such grids to the volume rendering engine Voreen. This project has three aims. Firstly, to implement new interpolation methods capable of rendering at interactive frame rates...

  12. Dynamic resolution in GPU-accelerated volume rendering to autostereoscopic multiview lenticular displays

    OpenAIRE

    Daniel Ruijters

    2009-01-01

    The generation of multiview stereoscopic images of large volume rendered data demands an enormous amount of calculations. We propose a method for hardware accelerated volume rendering of medical data sets to multiview lenticular displays, offering interactive manipulation throughout. The method is based on buffering GPU-accelerated direct volume rendered visualizations of the individual views from their respective focal spot positions, and composing the output signal for the multiview lenticu...

  13. Design and Implementation of an Application. Programming Interface for Volume Rendering

    OpenAIRE

    Selldin, Håkan

    2002-01-01

    To efficiently examine volumetric data sets from CT or MRI scans good volume rendering applications are needed. This thesis describes the design and implementation of an application programming interface (API) to be used when developing volume-rendering applications. A complete application programming interface has been designed. The interface is designed so that it makes writing application programs containing volume rendering fast and easy. The interface also makes created application progr...

  14. Stable Haptic Rendering for Physics Engines Using Inter-Process Communication and Remote Virtual Coupling

    OpenAIRE

    Xue-Jian He; Kup-Sze Choi

    2013-01-01

    Availability of physics engines has significantly reduced the effort required to develop interactive applications concerning the simulation of physical world. However, it becomes a problem when kinesthetic feedback is needed in the applications since the incorporation of haptic rendering is nontrivial, where fast haptic data update is demanded for stable rendering. In the regard, a framework for integrating haptic rendering into physics simulation engines is proposed. It mediates the update-...

  15. Frequency domain volume rendering by the wavelet X-ray transform

    OpenAIRE

    Westenberg, Michel A.; Roerdink, Jos B. T. M.

    2000-01-01

    We describe a wavelet-based X-ray rendering method in the frequency domain with a smaller time complexity than wavelet splatting. Standard Fourier volume rendering is summarized and interpolation and accuracy issues are briefly discussed. We review the implementation of the fast wavelet transform in the frequency domain. The wavelet X-ray transform is derived, and the corresponding Fourier-wavelet volume rendering algorithm (FWVR) is introduced. FWVR uses Haar or B-spline wavelets and linear ...

  16. Volume-Rendering-Based Interactive 3D Measurement for Quantitative Analysis of 3D Medical Images

    OpenAIRE

    Yakang Dai; Jian Zheng; Yuetao Yang; Duojie Kuai; Xiaodong Yang

    2013-01-01

    3D medical images are widely used to assist diagnosis and surgical planning in clinical applications, where quantitative measurement of interesting objects in the image is of great importance. Volume rendering is widely used for qualitative visualization of 3D medical images. In this paper, we introduce a volume-rendering-based interactive 3D measurement framework for quantitative analysis of 3D medical images. In the framework, 3D widgets and volume clipping are integrated with volume render...

  17. The problem of modern poetic rendering and editing of “The Tale of Igor's Campaign”

    Directory of Open Access Journals (Sweden)

    Temnuhin Valery

    2013-06-01

    Full Text Available The article is dedicated to the existing approaches to modern poetic rendering of the epic poem “The Tale of Igor's Campaign” (Slovo o polku Igoreve, misinterpretations of the original text in poetic translations, and requirements to be met in modern rendering of the epic poem intended for the rising generation in view of modern socio-political realities. The author presents his poem named “The Kayala” as a version of such modern rendering

  18. Development and evaluation of a Gal4-mediated LUC/GFP/GUS enhancer trap system in Arabidopsis

    OpenAIRE

    Schmuke Jon J; Fitzsimmons Karen C; Engineer Cawas B; Dotson Stan B; Kranz Robert G

    2005-01-01

    Abstract Background Gal4 enhancer trap systems driving expression of LacZ and GFP reporters have been characterized and widely used in Drosophila. However, a Gal4 enhancer trap system in Arabidopsis has not been described in the primary literature. In Drosophila, the reporters possess a Gal4 upstream activation sequence (UAS) as five repeats (5XUAS) and lines that express Gal4 from tissue specific enhancers have also been used for the ectopic expression of any transgene (driven by a 5XUAS). W...

  19. Arsenic Methylation in Arabidopsis thaliana Expressing an Algal Arsenite Methyltransferase Gene Increases Arsenic Phytotoxicity.

    Science.gov (United States)

    Tang, Zhong; Lv, Yanling; Chen, Fei; Zhang, Wenwen; Rosen, Barry P; Zhao, Fang-Jie

    2016-04-01

    Arsenic (As) contamination in soil can lead to elevated transfer of As to the food chain. One potential mitigation strategy is to genetically engineer plants to enable them to transform inorganic As to methylated and volatile As species. In this study, we genetically engineered two ecotypes of Arabidopsis thaliana with the arsenite (As(III)) S-adenosylmethyltransferase (arsM) gene from the eukaryotic alga Chlamydomonas reinhardtii. The transgenic A. thaliana plants gained a strong ability to methylate As, converting most of the inorganic As into dimethylarsenate [DMA(V)] in the shoots. Small amounts of volatile As were detected from the transgenic plants. However, the transgenic plants became more sensitive to As(III) in the medium, suggesting that DMA(V) is more phytotoxic than inorganic As. The study demonstrates a negative consequence of engineered As methylation in plants and points to a need for arsM genes with a strong ability to methylate As to volatile species. PMID:26998776

  20. Ectopic expression of Arabidopsis glycosyltransferase UGT85A5 enhances salt stress tolerance in tobacco.

    Directory of Open Access Journals (Sweden)

    Yan-Guo Sun

    Full Text Available Abiotic stresses greatly influence plant growth and productivity. While glycosyltransferases are widely distributed in plant kingdom, their biological roles in response to abiotic stresses are largely unknown. In this study, a novel Arabidopsis glycosyltransferase gene UGT85A5 was identified as significantly induced by salt stress. Ectopic expression of UGT85A5 in tobacco enhanced the salt stress tolerance in the transgenic plants. There were higher seed germination rates, better plant growth and less chlorophyll loss in transgenic lines compared to wild type plants under salt stress. This enhanced tolerance of salt stress was correlated with increased accumulations of proline and soluble sugars, but with decreases in malondialdehyde accumulation and Na(+/K(+ ratio in UGT85A5-expressing tobacco. Furthermore, during salt stress, expression of several carbohydrate metabolism-related genes including those for sucrose synthase, sucrose-phosphate synthase, hexose transporter and a group2 LEA protein were obviously upregulated in UGT85A5-expressing transgenic plants compared with wild type controls. Thus, these findings suggest a specific protective role of this glycosyltransferase against salt stress and provide a genetic engineering strategy to improve salt tolerance of crops.