Academic literature on the topic 'Shadow protein'
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Journal articles on the topic "Shadow protein"
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Wang, Siqi, Hui Zhao, and Yaping Zhang. "Advances in research on Shadoo, shadow of prion protein." Chinese Science Bulletin 59, no. 9 (January 28, 2014): 821–27. http://dx.doi.org/10.1007/s11434-014-0129-5.
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Kaller, Markus, Balint Földesi, and Wolfgang Nellen. "Localization and organization of protein factors involved in chromosome inheritance in Dictyostelium discoideum." Biological Chemistry 388, no. 4 (April 1, 2007): 355–65. http://dx.doi.org/10.1515/bc.2007.047.
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Abstract Heterochromatin protein 1 (HP1) proteins are highly conserved heterochromatin components required for genomic integrity. We have previously shown that the two HP1 isoforms expressed in Dictyostelium, HcpA and HcpB, are mainly localized to (peri-)centromeric heterochromatin and have largely overlapping functions. However, they cause distinct phenotypes when overexpressed. We show here that these isoforms display quantitative differences in dimerization behavior. Dimerization preference, as well as the mutant phenotype in overexpression strains, depends on the C-terminus containing the hinge and chromo shadow domains. Both Hcp proteins are targeted to distinct subnuclear regions by different chromo shadow domain-dependent and -independent mechanisms. In addition, both proteins bind to DNA and RNA in vitro and binding is independent of the chromo shadow domain. Thus, this DNA and/or RNA binding activity may contribute to protein targeting. To further characterize heterochromatin, we cloned the Dictyostelium homolog of the origin recognition complex subunit 2 (OrcB). OrcB localizes to distinct subnuclear foci that were also targeted by HcpA. In addition, it is associated with the centrosome throughout the cell cycle. The results indicate that, similar to Orc2 homologs from other organisms, it is required for different processes in chromosome inheritance.
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Smothers, James F., and Steven Henikoff. "The Hinge and Chromo Shadow Domain Impart Distinct Targeting of HP1-Like Proteins." Molecular and Cellular Biology 21, no. 7 (April 1, 2001): 2555–69. http://dx.doi.org/10.1128/mcb.21.7.2555-2569.2001.
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ABSTRACT Drosophila heterochromatin-associated protein 1 (HP1) is an abundant component of heterochromatin, a highly condensed compartment of the nucleus that comprises a major fraction of complex genomes. Some organisms have been shown to harbor multiple HP1-like proteins, each exhibiting spatially distinct localization patterns within interphase nuclei. We have characterized the subnuclear localization patterns of two newly discovered DrosophilaHP1-like proteins (HP1b and HP1c), comparing them with that of the originally described fly HP1 protein (here designated HP1a). While HP1a targets heterochromatin, HP1b localizes to both heterochromatin and euchromatin and HP1c is restricted exclusively to euchromatin. All HP1-like proteins contain an amino-terminal chromo domain, a connecting hinge, and a carboxyl-terminal chromo shadow domain. We expressed truncated and chimeric HP1 proteins in vivo to determine which of these segments might be responsible for heterochromatin-specific and euchromatin-specific localization. Both the HP1a hinge and chromo shadow domain independently target heterochromatin, while the HP1c chromo shadow domain is implicated solely in euchromatin localization. Comparative sequence analyses of HP1 homologs reveal a conserved sequence block within the hinge that contains an invariant sequence (KRK) and a nuclear localization motif. This block is not conserved in the HP1c hinge, possibly accounting for its failure to function as an independent targeting segment. We conclude that sequence variations within the hinge and shadow account for HP1 targeting distinctions. We propose that these targeting features allow different HP1 complexes to be distinctly sequestered in organisms that harbor multiple HP1-like proteins.
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Service, R. F. "BIOCHEMISTRY: Protein Arrays Step Out of DNA's Shadow." Science 289, no. 5485 (September 8, 2000): 1673. http://dx.doi.org/10.1126/science.289.5485.1673.
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Sánchez-Salguero, C. A. "Food Protein-Induced Proctocolitis. The shadow of allergic disorders." Allergologia et Immunopathologia 46, no. 1 (January 2018): 1–2. http://dx.doi.org/10.1016/j.aller.2017.10.002.
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Kingston-Smith, Alison H., Joan E. Edwards, Sharon A. Huws, Eun J. Kim, and Michael Abberton. "Plant-based strategies towards minimising ‘livestock's long shadow’." Proceedings of the Nutrition Society 69, no. 4 (August 4, 2010): 613–20. http://dx.doi.org/10.1017/s0029665110001953.
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Ruminant farming is an important component of the human food chain. Ruminants can use offtake from land unsuitable for cereal crop cultivation via interaction with the diverse microbial population in their rumens. The rumen is a continuous flow fermenter for the digestion of ligno-cellulose, with microbial protein and fermentation end-products incorporated by the animal directly or during post-ruminal digestion. However, ruminal fermentation is inefficient in capturing the nutrient resource presented, resulting in environmental pollution and generation of greenhouse gases. Methane is generated as a consequence of ruminal fermentation and poor retention of ingested forage nitrogen causes nitrogenous pollution of water and land and contributes to the generation of nitrous oxide. One possible cause is the imbalanced provision of dietary substrates to the rumen micro-organisms. Deamination of amino acids by ammonia-producing bacteria liberates ammonia which can be assimilated by the rumen bacteria and used for microbial protein synthesis. However, when carbohydrate is limiting, microbial growth is slow, meaning low demand for ammonia for microbial protein synthesis and excretion of the excess. Protein utilisation can therefore be improved by increasing the availability of readily fermentable sugars in forage or by making protein unavailable for proteolysis through complexing with plant secondary products. Alternatively, realisation that grazing cattle ingest living cells has led to the discovery that plant cells undergo endogenous, stress-mediated protein degradation due to the exposure to rumen conditions. This presents the opportunity to decrease the environmental impact of livestock farming by using decreased proteolysis as a selection tool for the development of improved pasture grass varieties.
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Devitt, Elizabeth. "Sun sets on protein initiative, casting shadow over drug discovery." Nature Medicine 19, no. 11 (November 2013): 1352. http://dx.doi.org/10.1038/nm1113-1352.
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Luijsterburg, Martijn S., Christoffel Dinant, Hannes Lans, Jan Stap, Elzbieta Wiernasz, Saskia Lagerwerf, Daniël O. Warmerdam, et al. "Heterochromatin protein 1 is recruited to various types of DNA damage." Journal of Cell Biology 185, no. 4 (May 18, 2009): 577–86. http://dx.doi.org/10.1083/jcb.200810035.
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Heterochromatin protein 1 (HP1) family members are chromatin-associated proteins involved in transcription, replication, and chromatin organization. We show that HP1 isoforms HP1-α, HP1-β, and HP1-γ are recruited to ultraviolet (UV)-induced DNA damage and double-strand breaks (DSBs) in human cells. This response to DNA damage requires the chromo shadow domain of HP1 and is independent of H3K9 trimethylation and proteins that detect UV damage and DSBs. Loss of HP1 results in high sensitivity to UV light and ionizing radiation in the nematode Caenorhabditis elegans, indicating that HP1 proteins are essential components of DNA damage response (DDR) systems. Analysis of single and double HP1 mutants in nematodes suggests that HP1 homologues have both unique and overlapping functions in the DDR. Our results show that HP1 proteins are important for DNA repair and may function to reorganize chromatin in response to damage.
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Kaye, Frederic J. "The Retinoblastoma-Like Protein Family: Still in the Shadow of the RB Gene?" JNCI: Journal of the National Cancer Institute 90, no. 19 (October 7, 1998): 1418–19. http://dx.doi.org/10.1093/jnci/90.19.1418.
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Anderson, M. S. "Projection of an Immunological Self Shadow Within the Thymus by the Aire Protein." Science 298, no. 5597 (October 10, 2002): 1395–401. http://dx.doi.org/10.1126/science.1075958.
Full textDissertations / Theses on the topic "Shadow protein"
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Premzl, Marko, and Premzl@anu edu au premzl@excite com Marko. "Prion Protein Gene and Its Shadow." The Australian National University. The John Curtin School of Medical Research, 2004. http://thesis.anu.edu.au./public/adt-ANU20050328.164529.
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Prion protein (PrP) is best known for its involvement in prion diseases. A normal, dynamic isoform of prion protein (PrP^C) transforms into a pathogenic, compact isoform (PrP^Sc) during prion disease pathogenesis. The PrP^Sc, acting as a template upon which PrP^C molecules are refolded into a likeness of itself, accumulates in the brain neurones and causes disease. It is the only known component of prions, proteinaceous infectious particles. Both prion protein isoforms have the same primary amino acid structure and are encoded by the same prion protein gene (PRNP). PRNP determines susceptibility/disposition to prion diseases and their phenotypes.¶The normal function of PRNP is elusive. The Prnp knock-out mice with disrupted ORF show only very subtle phenotype. A number of hypotheses were proposed on the function of mammalian PRNP. The extracellular, GPI-anchored, glycosylated mammalian PrP^C expressed in a heterogenous set of cells could: transport copper from extracellular to intracellular milieu, buffer copper from synapse, contribute to redox signalling, act neuroprotectively, mediate cell-cell contacts, affect lymphocyte activation, participate in nucleic acid metabolism, be a memory molecule, and be a signal-transduction protein.¶ Experimental evidence demonstrated a redundancy between the PRNP and another, unknown gene. The critical issue therefore is to discover new genes homologous with PRNP, candidates for this redundancy. Using unpublished data, a sequence of zebrafish cDNA sequenced by Prof. Tatjana Simonics group (University of Milan, Italy), I discovered a new paralogue of PRNP. By searching manually, and in a targeted fashion, data deposited in public biological databases, I compiled support for the new human gene Shadow of prion protein (SPRN) including the direct evidence, homology-based evidence and ab initio gene prediction. The protein product called Shadoo (shadow in Japanese) is an extracellular, potentially glycosylated and GPI-anchored protein of a mature size of 100-odd amino acids. It is conserved from fish (zebrafish, Fugu, Tetraodon) to mammals (human, mouse, rat), and exhibits similarity of overall protein features with PrP. Most remarkably, the Sho is the first human/mammalian protein apart from PrP that contains the middle hydrophobic region that is essential for both normal and pathogenic properties of PrP. As this region is critical for heterodimerization of PrP, Sho may have potential to interact with PrP and is a likely candidate for the Protein X. Mammalian SPRN could be predominantly expressed in brain (Tatjana Simonic Lab, University of Milan, Italy).¶ Using the same approach to search public databases, I found, in addition, a fish duplicate of SPRN called SPRNB, and defined a new vertebrate SPRN gene family. Further, I also expanded a number of known fish genes from the PRNP gene family. The total number of the new genes that I discovered is 11. With the representatives of two vertebrate gene family datasets in hand, I conducted comparative genomic analysis in order to determine evolutionary trajectories of the SPRN and PRNP genes. This analysis, complemented with phylogenetic studies (Dr. Lars Jermiin, University of Sydney, Australia), demonstrated conservative evolution of the mammalian SPRN gene, and more relaxed evolutionary constraints acting on the mammalian PRNP gene. This evolutionary dialectic challenges widely adopted view on the highly conserved vertebrate PRNP and indicates that the SPRN gene may have more prominent function. More conserved Sprn could therefore substitute for the loss of less conserved, dispensable Prnp in the Prnp knock-out mice. Furthermore, the pathogenic potential of PRNP may be a consequence of relaxed evolutionary constraints.¶ Depth of comparative genomic analysis, strategy to understand biological function, depends on the number of species in comparison and their relative evolutionary distance. To understand better evolution and function of mammalian PRNP, I isolated and characterized the PRNP gene from Australian model marsupial tammar wallaby (Macropus eugenii). Marsupials are mammals separated from their eutherian relatives by roughly 180 million years. Comparison of the tammar wallaby and Brazilian opossum PrP with other vertebrate PrPs indicated patterns of evolution of the PrP regions. Whereas the repeat region is conserved within lineages but differs between lineages, the hydrophobic region is invariably conserved in all the PrPs. Conservation of PrP between marsupials and eutherians suggests that marsupial PrP could have the same pathogenic potential as eutherian PrPs. Using the marsupial PRNP gene in comparison with the PRNP genes from eutherian species in which prion diseases occur naturally (human, bovine, ovine) or experimentally (mouse), I defined gene regions that are conserved mammalian-wide and showed the utility of the marsupial genomic sequence for cross-species comparisons. These regions are potential regulatory elements that could govern gene expression and posttranscriptional control of mRNA activity. These findings shed new light on the normal function of mammalian PRNP supporting best the signal-transduction hypothesis. The normal function of PRNP may be triggering of signalling cascades which contribute to cell-cell interactions and may act anti-apoptotically. Yet, in the heterogenous set of cells expressing PrP^C these pathways will contribute to a number of cell-specific phenotypes, such as the synaptic plasticity and activation of lymphoid cells.
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Sakthivelu, Vignesh. "Functional characterization of Shadoo, a PrP-like protein with neuroprotective activity." Diss., lmu, 2012. http://nbn-resolving.de/urn:nbn:de:bvb:19-144326.
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Gajic, Ciric Danica. "Biochemical and structural study of Shadoo protein and its interaction with PrP." Paris 7, 2014. http://www.theses.fr/2014PA077150.
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La protéine Shadoo (Sho) appartient à la famille des. Protéines prion. Les protéines Sho et PrP partagent de nombreuses similitudes, allant de leur co-localisation anatomo-histologique à une forte similarité de séquence. L'inhibition de l'expression de Sho durant l'infection à prion, ainsi que l'interaction entre ses deux protéines observée par double hydride, laissent suggérer une relation étroite entre ses deux protéines pendant la phase de réplication du prion. L'objectif de ce travail de thèse est d'explorer le rôle de la protéine Sho dans la dynamique conformationnelle de PrP, ainsi que l'effet d'une telle interaction sur le phénomène de réplication. La caractérisation de la structure secondaire de montre que Sho est une protéine naturellement désordonnée entre les pH 3. 5 et 8. Le spectre RMN de Sho correspond au spectre typique des protéines non repliées, même-si Sho semble adopter une structure organisée localement au niveau du segment C-terminal. D'autre part, l'utilisation de technique de biochimies et de biophysiques nous ont permis de démontrer que Sho et PrP formaient un complexe 1 :1 avec un Kd de l'ordre du micromolaire. Cette interaction a pour conséquence une altération du repliement de PrP. L'utilisation de la forme tronquée de PrP, mimant le fragment Cl, nous a permis d'observer une liaison allostérique avec un nombre de hill de 4, une tétramérisation. La co-polymérisation semble avoir pour conséquence une augmentation du pouvoir infectieux des particules prion en culture de cellules. Nos résultats montre que la protéine Sho affecte la réplication du prion, soit en agissant comme une holdase, soit en interférant avec le rôle protecteur du fragment ClShadoo (Sho) protein belongs to prion protein family. From the histo-anatomical co-localization and sequence similarities, it is suspected that Sho and PrP may be functionally related. Down regulation of Sho expression during prion pathology in one hand, and direct interaction between Sho and PrP, revealed by two-hybrid assay, suggests a relation between Sho and prion replication. The objective of this PhD thesis was to explore involvement of Sho in conformational dynamics of PrP and its effect on conversion process involved in prion replication. Secondary structure characterization of Sho revealed that Sho is a disordered protein between 3. 5
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Meneghini, Rafael Cedric Möller. "Ferramenta para maximização do lucro de laticínios pelo planejamento do mix ótimo de produtos lácteos e precificação dos componentes do leite cru." Universidade de São Paulo, 2014. http://www.teses.usp.br/teses/disponiveis/11/11139/tde-30042014-113554/.
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Pequenos e médios laticínios têm grandes dificuldades no planejamento da produção para maximizar o lucro. Além disso, a forma atual de precificar o leite cru no Brasil desestimula o produtor a melhorar sua qualidade, pois valoriza mais seu volume do que seus componentes sólidos. A composição do leite cru é muito importante para os laticínios, pois ela afeta diretamente o rendimento de produção e a qualidade dos produtos lácteos. Técnicas de otimização, como programação linear (PL), ajudam a resolver problemas relacionados à decisão do mix de produtos, além de fazer análise econômica dos recursos. Em razão disso, foi desenvolvido em PL um modelo para maximização da margem de contribuição total (MCT = receita total das vendas - custos e despesas diretas totais) e precificação do leite cru através da determinação do mix ótimo de produtos lácteos. O modelo foi simulado em cenários diários de alta (Janeiro) e baixa (Julho) disponibilidade de matéria prima comparando as soluções ótimas com resultados reais de um laticínio do sudeste do Brasil. Foram realizadas análises de sensibilidade dos componentes nutritivos de dois tipos de leite cru de diferentes composições (LC1, leite cru proveniente de um fornecedor, e LC50, leite cru proveniente de 50 fornecedores) para determinar seus preços-sombra. Foram observados preços-sombra para o quilograma da caseína em Janeiro e Julho e para o litro do LC50 em Julho. A MCT ótima e os preços calculados de ambos os tipos de leite cru foram maiores em Janeiro devido à maior disponibilidade de matéria prima. Em ambos os cenários, os preços calculados de ambos os tipos de leite cru foram maiores que os praticados pelo laticínio e o lucro antes de juros, impostos, depreciação e amortização (LAJIDA) diário real foi maior que o ótimo. A embaladora foi um recurso limitante atuante na produção do queijo Minas Frescal nos mixes ótimos. A relação entre margem de contribuição unitária (MCU = preço unitário de venda - custo e despesa diretos unitários) e quantidade necessária de matéria prima por unidade de produto e a disponibilidade de recursos são determinantes na definição do mix de produtos lácteos e da MCT do laticínio. A precificação do leite cru pelo modelo proposto remunera o produtor em função da quantidade de seus componentes. O laticínio pode maximizar seu LAJIDA planejando melhor seu mix de produtos com PL e remunerando melhor seus fornecedores em função da qualidade do leite cru.Small and medium-sized dairies face great difficulties in production planning to maximize profit. In addition, the current way of pricing the raw milk in Brazil discourages producers to improve its quality because its volume values more than its solid components. The raw milk composition is very important for the dairies because it directly affects the yield and quality of dairy products. Optimization techniques, such as linear programming (LP), aid solve problems related to the decision of the product mix and perform economic analyzes of resources. For this reason, a model was developed in LP to maximizing total contribution margin (TCM = total sales revenues - total variable costs and expenses) and pricing the raw milk by determining the optimal mix of dairy products. The model was simulated in two daily scenarios of high (January) and low (July) availability of raw material comparing the optimal solutions with actual results from a dairy plant in Southeastern Brazil. Sensitivity analyzes of the nutritional components of two kinds of raw milk of different compositions (RM1 and RM50) were performed to determine their shadow-prices. Shadow-prices were observed for the kilogram of casein in January and July and for the liter of RM50 in July. The optimal TCM and the calculated prices of both types of raw milk were higher in January due the increased availability of raw materials. In both scenarios, the calculated prices of both types of raw milk were higher than those paid by the dairy plant and the actual daily earnings before interests, taxes, depreciation and amortization (EBITDA) were greater than the optimum ones. The wrapper was an active limiting resource in the production of Frescal Minas cheese in optimal mixes. The relationship between unit contribution margin (UCM = unit sales price - unit variable cost and expense) and required amount of raw material per unit of output and resource availability are crucial in defining the mix of dairy products and the dairy TCM. The proposed raw milk pricing model pays the producer by the quantity of its components. The dairies can maximize their EBITDA planning their product mixes with LP and remunerating their suppliers based on the quality of raw milk.
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Blanco, Touriñán Noel. "New mechanisms of DELLA protein regulation and activity in Arabidopsis." Doctoral thesis, Universitat Politècnica de València, 2020. http://hdl.handle.net/10251/149477.
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[EN] DELLA proteins are plant-specific transcriptional regulators known to relay environmental information to the transcriptional networks to modulate growth and development accordingly. The view of DELLAs as signalling hubs is justified by two characteristics: first, they control the activity of a large number of transcriptional factors (TFs) and other transcriptional regulators through physical interaction; and, second, they are degraded by the 26S proteasome in response to the phytohormone gibberellin (GA), whose metabolism is very sensitive to environmental stimuli (e.g. light, temperature, salt stress). However, at least two observations indicate that this mechanistic framework is still incomplete: (i) warm temperature destabilizes the GA-insensitive DELLA rga-¿17, indicating that DELLAs cannot be destabilized only by changes in GA levels; and (ii) when found at the chromatin, DELLAs are localized not only in gene promoters, but also in gene bodies, suggesting that DELLAs may regulate transcription through interactions with proteins other than TFs. In this Thesis, we provide evidence that shows how a different E3 ubiquitin ligase controls the stability of DELLAs in a GA-independent manner, and how DELLAs regulate gene expression by directly interacting with the basal transcriptional machinery. In the first chapter, using a combination of genetic, physiological, and molecular approaches we demonstrate that DELLAs are targeted to proteolytic degradation by the E3 ubiquitin ligase CONSTITUTIVELY PHOTOMORPHOGENIC 1 (COP1). We show that COP1 interacts with the DELLAs GAI and RGA in vitro and in vivo, and that it promotes their polyubiquitination. We propose that COP1 represents a major pathway to degrade DELLAs in response to shade or to warm temperature. In the second chapter, we describe the interaction between DELLAs and the transcription elongation complex Polymerase-Associated Factor 1 (Paf1c). We show that Paf1c is required for the genome-wide deposition of monoubiquitinated H2B (H2Bub), a mark necessary for the progression of RNA polymerase II (RNAPII), and that this function is largely dependent on the presence of DELLAs. Likewise, impaired Paf1c or DELLA function results in a similar alteration in the accumulation and distribution of RNAPII in the Paf1c-target genes. We propose that DELLAs would exert this action by modulating the recruitment of Paf1c to the chromatin.
These two new mechanisms underscore the importance of DELLAs as a central node in the environmental signalling network and should be considered in any potential application of DELLAs as biotechnological targets.[ES] Las proteínas DELLA son reguladores transcripcionales específicos de plantas que transmiten información ambiental a las redes transcripcionales que modulan el crecimiento y el desarrollo. La propuesta de que las DELLAs actúan como "hubs" en redes de señalización se justifica por dos razones: primero, controlan la actividad de un gran número de factores de transcripción (FTs) y otros reguladores transcripcionales mediante interacción física; y segundo, son degradadas por el proteosoma 26S en respuesta a la fitohormona giberelina (GA), cuyo metabolismo es muy sensible a los estímulos ambientales (p. ej. luz, temperatura, estrés salino). Sin embargo, al menos dos observaciones sugieren que la información relativa a estos mecanismos no es completa: (i) las temperaturas altas desestabilizan incluso a rga-¿17, una versión de DELLA insensible a GAs, lo que indica que la estabilidad de las DELLAs no depende sólo de cambios en los niveles de GAs; y (ii) cuando se encuentran en la cromatina, las DELLAs no solo se posicionan en los promotores, sino también a lo largo de las regiones codificantes, lo que sugiere que las DELLAs podrían regular la transcripción mediante interacciones con otras proteínas diferentes a FTs. En esta Tesis, proporcionamos evidencia sobre una nueva E3 ubicuitina ligasa que controla la estabilidad de las DELLAs de una manera independiente a las GAs, y cómo las DELLA regulan la expresión génica interaccionando directamente con la maquinaria de transcripción basal. En el primer capítulo, usando una combinación de aproximaciones genéticas, fisiológicas y moleculares, demostramos que las DELLAs son marcadas para su degradación proteolítica por la E3 ubicuitina ligasa CONSTITUTIVELY PHOTOMORPHOGENIC 1 (COP1). Mostramos que COP1 interacciona al menos con las DELLAs GAI y RGA in vitro e in vivo, y que promueve su poliubicuitinación. Proponemos que COP1 representa una vía importante de degradación de DELLAs en respuesta a sombra y temperaturas altas. En el segundo capítulo, describimos la interacción entre las DELLAs y el complejo de elongación transcripcional Polymerase-Associated Factor 1 (Paf1c). Mostramos que, como en animales, Paf1c se requiere para la deposición a nivel genómico de la H2B monoubiquitinada (H2Bub), una marca necesaria para la progresión de la RNA polimerasa II (RNAPII), y que esta función depende en gran medida de la presencia de DELLAs. Asimismo, la reducción de la función de las DELLAs provoca defectos equivalentes a los de la pérdida de función de Paf1c en cuanto a la acumulación y distribución de la RNAPII en los genes diana de Paf1c. Proponemos que las DELLAs podrían por tanto regular la transcripción modulando el reclutamiento de Paf1c a la cromatina. Estos nuevos mecanismos inciden en la importancia de las DELLAs como nodos centrales en las redes de señalización al ambiente y podrían ser considerados como dianas biotecnológicas en aproximaciones futuras.
[CA] Les proteïnes DELLA són reguladors transcripcionals específics de les plantes conegudes per transmetre informació mediambiental a les xarxes transcripcionals per modular el creixement i desenvolupament. La visió actual de DELLAs com a "hubs" de senyalització es justifica per dues característiques: en primer lloc, controlen l'activitat d'un gran nombre de factors transcripcionals (FTs) i d'altres reguladors transcripcionals mitjançant la interacció física; i, en segon lloc, es degraden pel proteosoma 26S en resposta a la fitohormona giberel.lina (GA), el metabolisme de la qual és molt sensible als estímuls ambientals (per exemple, la llum, la temperatura, l'estrès salí). No obstant això, almenys dues observacions indiquen que aquest marc mecanicista encara és incomplet: (i) la temperatura càlida desestabilitza la DELLA rga-¿17, que és insensible a GAs, indicant que les DELLA no es desestabilitzen només per canvis en els nivells d'aquesta fitohormona; i (ii) quan es troben a la cromatina, les DELLA no només es localitzen en els promotors dels gens, sinó també a la regió que es transcriu, cosa que suggereix que poden regular la transcripció mitjançant interaccions amb proteïnes diferents de FTs. En aquesta tesi, proporcionem evidències que mostren com una ubiquitina E3 lligasa diferent controla l'estabilitat de les proteïnes DELLA de manera independent de GAs, i com les DELLA regulen l'expressió gènica interactuant directament amb la maquinària transcripcional basal. En el primer capítol, mitjançant una combinació d'enfocaments genètics, fisiològics i moleculars, demostrem que les DELLA s'envien a la degradació proteolítica mitjançant la ubiquitina E3 lligasa CONSTITUTIVELY PHOTOMORPHOGENIC 1 (COP1). Mostrem que la COP1 interacciona amb els DELLA GAI i RGA in vitro i in vivo, i que afavoreix la seva poliubiquitinació. Proposem que COP1 representa la via principal per degradar les DELLA en resposta a l'ombra o a la temperatura càlida. Al segon capítol, es descriu la interacció entre les DELLA i el complex d'allargament de transcripció Polymerase Associated Factor 1 (Paf1c). Mostrem que Paf1c es requereix per a la deposició a tot el genoma de H2B monoubiquitinada (H2Bub), una marca necessària per a la progressió de l'ARN Polimerasa II (RNAPII), i que aquesta funció depèn en gran part de la presència de DELLA. De la mateixa manera, quan la funció Paf1c o DELLA està deteriorada, es produeix una alteració similar en l'acumulació i distribució de RNAPII als gens diana de Paf1c. Proposem que les DELLA realitzen aquesta acció modulant el reclutament de Paf1c a la cromatina. Aquests dos nous mecanismes posen de manifest la importància de les proteïnes DELLA com a node central de la xarxa de senyalització ambiental i haurien de ser considerats en qualsevol aplicació potencial de DELLA com a objectius biotecnològics.
La realización de esta Tesis Doctoral ha sido posible gracias a un contrato predoctoral para la formación de doctores (BES-2014-068868) y a la ayuda a la movilidad predoctoral para la realización de estancias breves (EEBB-I-16-11070) del Ministerio de Economía y Competitividad, y a una beca EMBO Short-Term (number 8047).
Blanco Touriñán, N. (2020). New mechanisms of DELLA protein regulation and activity in Arabidopsis [Tesis doctoral no publicada]. Universitat Politècnica de València. https://doi.org/10.4995/Thesis/10251/149477
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Sakthivelu, Vignesh [Verfasser], and Jörg [Akademischer Betreuer] Tatzelt. "Functional characterization of Shadoo, a PrP-like protein with neuroprotective activity / Vignesh Sakthivelu. Betreuer: Jörg Tatzelt." München : Universitätsbibliothek der Ludwig-Maximilians-Universität, 2012. http://d-nb.info/1023661055/34.
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Shao, Lin [Verfasser], and Jörg [Akademischer Betreuer] Nickelsen. "Characterization of the TPR protein family and a putative photosynthetic protein from Synechocystis PCC 6803 / Lin Shao. Betreuer: Jörg Nickelsen." München : Universitätsbibliothek der Ludwig-Maximilians-Universität, 2012. http://d-nb.info/1049393295/34.
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Qu, Xiaoguang. "NMR Study of Structure and Orientation of S4-S5 Linker Peptides from Shaw Related Potassium Ion Channels in Micelles and Binding of ZNF29R Protein to HIV RREIIBTR RNA." Digital Archive @ GSU, 2009. http://digitalarchive.gsu.edu/chemistry_diss/33.
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Potassium ion channels play a key role in the generation and propagation of action potentials. The S4-S5 linker peptide (L45) is believed to be responsible for the anesthetic/alcohol response of voltage-gated K+ channels. We investigated this region to define the structural basis of 1-alkanol binding site in dShaw2 K+ channel. L45 peptides derived from dShaw2 and hKv3.4 K+ channel, which, if part of the complete channel, demonstrate different sensitivity to 1-alcohols. Specifically, dShaw2 is alcohol sensitive and hKv3.4 is alcohol resistant. Structural analysis of L45 with NMR and CD suggested a direct correlation between alpha-helicity and the inhibition of dShaw2 channel by 1-butanol. We used CD and NMR to determine the structure of L45 peptides in micelles and vesicles. We measured spin-lattice relaxation time (T1) and determined the location and surface accessibility of L45 in micelles. These experiments confirm that L45 of dShaw2 adopts an α-helical conformation, partially buried in the membrane and parallel to the surface. The binding and accumulation of rev proteins to an internal loop of RRE (rev responsive element) of unspliced mRNA precursors is a key step of propagation of human immunodeficiency (HIV) virus. Molecules that interfere with this process can be expected to show anti-HIV activity. Our work is based on an assumption that zinc fingers could compete with rev proteins, therefore impeding the life cycle of HIV and stopping its infection. We studied the influence of different cations, anions, and the concentration of salts and osmolytes on the binding affinity with Polyacrylamide Gel Electrophoresis (PAGE) and Isothermal Titration Calorimetry (ITC). We conclude that the types of anions and/or cations and their concentrations affect the enthalpy and entropy of the binding interacitons. Using a gel assay, we confirm that there are three products in RNA-Protein reaction, and both EDTA and salts (and their concentrations) in the gel or samples interfere with RNA-protein complex mobility.
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Gonçalves, Gislei Cristina. "Cultivo em campo de Coffea arabica L. cv. Obatã a pleno sol x sombreamento parcial: avaliações bioquímicas, fisiológicas e nutricionais." Universidade de São Paulo, 2007. http://www.teses.usp.br/teses/disponiveis/11/11144/tde-14052007-160536/.
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Plantas de café Arábicas com 4,5 anos de idade foram comparadas de agosto a dezembro crescendo a pleno sol e sob condições de sombreamento natural. As plantas apresentaram diferenças significativas em termos de crescimento e aspectos fisiológicos e bioquímicos O fornecimento de nitrogênio no mês de outubro proporcionou um aumento significativo nos teores de aminoácidos totais e na atividade da redutase do nitrato. As folhas de plantas crescendo em condições de sombreamento natural apresentaram maior peso fresco a que pleno sol. O teor de proteínas totais decresceu abruptamente a partir do mês 10 em todas as plantas analisadas, época em coincidiu com o inicio do enchimento dos grãos. O aumento nos teores de aminoácidos totais também foi acompanhado por um aumento nos dias de chuva, na precipitação e também na radiação global. Não houve efeito significativo com relação á localização da folhas (parte superior x parte inferior) nos aspectos analisados. O fornecimento de nitrogênio no mês 10 não alterou a concentração de clorofila medida pelo clorofilômetro SPAD, e a clorofila total extraída não se alterou significativamente até o mês 11 exceto nas plantas de sol as folhas do parte superior tiveram uma maior síntese no mês 9. No mês 12 houve um aumento nas taxas de clorofila em todos os tratamentos. Os teores de N foliar tiveram correlação positiva com as leituras de clorofila analisadas pelo SPAD, ate o mês 11. Tivemos também no período de analise, um aumento significativo na concentração de carotenóides a partir do mês 8, evidenciando seu efeito foto protetor uma vez que houve também um aumento na radiação global no período ao redor de 50%. As folhas em condições de sombreamento natural apresentaram maior peso seco que as de pleno sol. O teor de proteínas totais decresceu abruptamente a partir do mês 11 em todas as plantas, época que coincidiu com o início da produção/enchimento dos grãos. Houve um aumento nos teores de amido após o mês 10 (exceto nas folhas da parte inferior das plantas de sol), vindo a diminuir em função do enchimento dos grãos. Também se observou uma síntese acentuada de açúcares redutores no início, decrescendo em função do início da formação dos grãos. Com relação aos nutrientes nas folhas analisadas, o manganês teve um comportamento significativamente diferente em relação aos demais, onde nas folhas a pleno sol a concentração do elemento foi de 6 a 8 vezes á das folhas sombreadas.Plants of Arabian coffee with 4,5 years of age, had been compared from August to December growing under full sun and under natural shade conditions. The plants presented significant differences in growth terms and physiological and biochemical's aspects. The nitrogen supply in the October month provided a significant increase on levels of amino acid totals and the activity of nitrate redutase. The leaves of plants growing under natural shade presented greater fresh weight than full sun. The total protein levels abruptly decreased from the month 10 in all analyzed plants, time in coincidence with the beginning of filling up the grains. The increase on levels of total amino acids also was followed by an increase in the days of rain, the precipitation and also the global radiation. Didn't have significant effect with relation of localization of leaves (upper part X inferior part) within analyzed aspects. The nitrogen supply in month 10 did not modify the concentration of chlorophyll measured by chlorophyll meter SPAD, and chlorophyll total extracted did not change significantly until month 11 except in the sunny plants leaves of upper part that had a bigger synthesis in month 9. In month 12 had an increase on the levels of chlorophyll in all the treatments. The levels of foliar N had had positive correlation with the readings of chlorophyll analyzed by the SPAD, until month 11. We had also in the period of analyzes, a significant increase on the concentration of carotenoids from month 8, evidencing its photo protective effect. During this time also we had an increase in the global radiation in the period around 50%. The leaves in conditions of natural shade had presented greater dry weight that of full sun. The total protein levels abruptly decreased from the month 11 in all plants, time coincident with the beginning of the production/filling up of the grains. The Month 10 also had an increase in starch levels (except in leaves of third inferior of the sunny plants), decreasing in function of the filling up of the grains. Also an increased synthesis of reducing sugars was observed at the beginning and a decrease during the beginning of the formation of the grains. With regard to the nutrients in analyzed leaves, the manganese had a behavior significantly different in relation to others, where in leaves at the full sun the concentration of the element was 6 to 8 times higher than shaded leaves.
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AL-Rawi, Shadha [Verfasser], Joerg [Akademischer Betreuer] Fettke, Alisdair [Akademischer Betreuer] Fernie, Christophe [Gutachter] D’Hulst, and Oluwatoyin A. [Gutachter] Odeku. "Biochemical studies to determine the role of Early Starvation 1 (ESV1) protein and its homologue Like-Early Starvation 1 (LESV) during starch degradation / Shadha AL-Rawi ; Gutachter: Christophe D’Hulst, Oluwatoyin A. Odeku ; Joerg Fettke, Alisdair Fernie." Potsdam : Universität Potsdam, 2020. http://d-nb.info/1223536769/34.
Full textBooks on the topic "Shadow protein"
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Shades of justice: A memoir. Altadena, Calif: Autumn Leaf Press, 2008.
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Tsel ʻolam =: World shadow. 2013.
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Clarke, Andrew. Freezing. Oxford University Press, 2017. http://dx.doi.org/10.1093/oso/9780199551668.003.0006.
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Freezing is a widespread ecological challenge, affecting organisms in over half the terrestrial environment as well as both polar seas. With very few exceptions, if a cell freezes internally, it dies. Polar teleost fish in shallow waters avoid freezing by synthesising a range of protein or glycoprotein antifreezes. Terrestrial organisms are faced with a far greater thermal challenge, and exhibit a more complex array of responses. Unicellular organisms survive freezing temperatures by preventing ice nucleating within the cytosol, and tolerating the cellular dehydration and membrane disruption that follows from ice forming in the external environment. Multicellular organisms survive freezing temperatures by manipulating the composition of the extracellular body fluids. Terrestrial organisms may freeze at high subzero temperatures, often promoted by ice nucleating proteins, and small molecular mass cryoprotectants (often sugars and polyols) moderate the osmotic stress on cells. A range of chaperone proteins (dehydrins, LEA proteins) help maintain the integrity of membranes and macromolecules. Thermal hysteresis (antifreeze) proteins prevent damaging recrystallisation of ice. In some cases arthropods and higher plants prevent freezing in their extracellular fluids and survive by supercooling. Vitrification of extracellular water, or of the cell cytosol, may be a more widespread response to very cold temperatures than recognised to date.
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To Love and Protect: Shadow Chasing for All My Tomorrows. Harlequin Enterprises, Limited, 2014.
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Arab Spring: Negotiating in the Shadow of the Intifadat. University of Georgia Press, 2015.
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Zartman, I. William, Mark Anstey, Samir Aita, and Alice Alunni. Arab Spring: Negotiating in the Shadow of the Intifadat. University of Georgia Press, 2015.
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Yoder, Perry. Shalom: The Bible's Word for Salvation, Justice, and Peace. Wipf & Stock Publishers, 2017.
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Yoder, Perry. Shalom: The Bible's Word for Salvation, Justice and Peace. Spire, 1989.
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Shalom: The Bible's Word for Salvation, Justice, and Peace. Wipf & Stock Publishers, 2017.
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Out of Mao's Shadow: The Struggle for the Soul of a New China. Picador USA, 2009.
Find full textBook chapters on the topic "Shadow protein"
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Eissenberg, Joel C., and Sepideh Khorasanizadeh. "Chromo and Chromo Shadow Domains." In Modular Protein Domains, 241–55. Weinheim, FRG: Wiley-VCH Verlag GmbH & Co. KGaA, 2005. http://dx.doi.org/10.1002/3527603611.ch12.
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Westaway, David, Nathalie Daude, Serene Wohlgemuth, and Paul Harrison. "The PrP-Like Proteins Shadoo and Doppel." In Topics in Current Chemistry, 225–56. Berlin, Heidelberg: Springer Berlin Heidelberg, 2011. http://dx.doi.org/10.1007/128_2011_190.
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Matos, Sérgio. "Improving Document Prioritization for Protein-Protein Interaction Extraction Using Shallow Linguistics and Word Embeddings." In Advances in Intelligent Systems and Computing, 43–49. Cham: Springer International Publishing, 2017. http://dx.doi.org/10.1007/978-3-319-60816-7_6.
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Pan, Zhigeng, Shusen Sun, Jian Yang, and Xiaochao Wei. "Protect Interactive 3D Models via Vertex Shader Programming." In Entertainment Computing - ICEC 2005, 59–66. Berlin, Heidelberg: Springer Berlin Heidelberg, 2005. http://dx.doi.org/10.1007/11558651_6.
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Vinnell, Martin P., Christine A. Raines, and Neil R. Baker. "Response of Thylakoid Membrane Proteins During Shade-Adaptation in Silene Dioica." In Photosynthesis: from Light to Biosphere, 2611–14. Dordrecht: Springer Netherlands, 1995. http://dx.doi.org/10.1007/978-94-009-0173-5_615.
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Koenig, Friederike. "Development of Shade-Type Appearance — Light Intensity Adaptation — and Regulation of the D1 Protein in Synechococcus." In Regulation of Chloroplast Biogenesis, 545–50. Boston, MA: Springer US, 1992. http://dx.doi.org/10.1007/978-1-4615-3366-5_79.
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Koenig, Friederike. "Different Amino Acid Exchanges in the Dl Protein Cause Different Degrees of Shade Type Appearance in Herbicide Tolerant Anacystis." In Current Research in Photosynthesis, 3167–70. Dordrecht: Springer Netherlands, 1990. http://dx.doi.org/10.1007/978-94-009-0511-5_714.
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"Shadows of War." In Protest at Midnight, 112–24. African Sun Media, 2022. http://dx.doi.org/10.2307/j.ctv2svjxn1.19.
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Konove, Andrew. "Shadow Economics." In Black Market Capital, 61–87. University of California Press, 2018. http://dx.doi.org/10.1525/california/9780520293670.003.0004.
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This chapter moves from an analysis of elite debates over urban renewal to an examination of the quotidian transactions of the Baratillo in the eighteenth and early nineteenth centuries. The shadow economy linked baratilleros to some of Mexico’s elite overseas merchants while pitting them against the capital’s artisan guilds and shopkeepers, who saw them as disloyal competition. In reconstructing these relationships, the chapter reveals the centrality of the Baratillo’s commerce to the late-colonial urban economy. It also illustrates the ways that economics and politics intertwined in the market, as vendors pursued multiple strategies to protect their businesses from outside threats.
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Bell, Derrick. "Plessy’s Long Shadow." In Silent Covenants. Oxford University Press, 2004. http://dx.doi.org/10.1093/oso/9780195172720.003.0005.
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The supreme court’s 1896 Decision in Plessy v. Ferguson served to bring the law into a dismal harmony with the nation’s view of race in life. The Court decided that segregation in public facilities through “separate but equal” accommodations for black citizens would satisfy the equal protection clause in the Fourteenth Amendment. The years since the sporadically enforced policies of Reconstruction ended in 1876 had been hard for those former slaves and their offspring whose slavery had legally ended with the passage of the Thirteenth Amendment in 1865. To ensure their rights to due process and the equal protection of the law, the Fourteenth Amendment in 1868 provided that “all persons born or naturalized in the United States, . . . are citizens of the United States and of the State wherein they reside.” Despite legislation intended to provide enforcement of these rights, the laws were poorly enforced and most were subsequently declared unconstitutional. Corrupting law but relying on intimidation and violence, southern governments stripped blacks of political power. Given meaningful if unspoken assurances that the federal government would not protect black civil rights, conservative southerners regained power utilizing racial fear and hatred to break up competing populist groups of poor black and white farmers. In addition to the disenfranchisement of blacks, whites sought to secure their power through intensive anti-Negro propaganda campaigns championing white supremacy. Literary and scientific leaders published tracts and books intended to “prove” the inhumanity of the Negro. In this hostile climate, segregation laws that had made a brief appearance during Reconstruction were revived across the South, accompanied by waves of violence punctuated by an increase in lynchings and race riots. In an effort both to protest the indignity of segregation and challenge its validity, Homer Plessy, acting for a New Orleans civil rights group, attempted to ride in a railroad car reserved for whites. He was arrested and convicted of violating Louisiana’s 1890 segregation law. On appeal, the Supreme Court acknowledged that the Fourteenth Amendment required absolute equality of the two races before the law, adding: “but in the nature of things it could not have been intended to abolish distinctions based upon color, or to enforce social, as distinguished from political equality, or a commingling of the two races upon terms unsatisfactory to either.”
Conference papers on the topic "Shadow protein"
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Cheng, Q., and K. Komvopoulos. "Surface Chemical Patterning for Controlled Cell Adhesion." In ASME/STLE 2009 International Joint Tribology Conference. ASMEDC, 2009. http://dx.doi.org/10.1115/ijtc2009-15134.
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Thin films exhibiting nonfouling behavior toward protein and cell attachment were grafted onto different substrates by plasma polymerization and deposition. By combining nonfouling film grafting and partial film etching by Ar ion sputtering through the windows of a shadow mask (Si or PDMS), chemical patterns of different shapes and sizes were produced on polymer substrates. Results from cell culture studies illustrate the effectiveness of the present fabrication process to produce surface micropatterns for controlling the cell shape and morphology, with direct implications in vascular pathology.
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Yu, Huanhuan, Longhua Qian, Guodong Zhou, and Qiaoming Zhu. "Extracting Protein-Protein Interaction from Biomedical Text Using Additional Shallow Parsing Information." In 2009 2nd International Conference on Biomedical Engineering and Informatics. IEEE, 2009. http://dx.doi.org/10.1109/bmei.2009.5302220.
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Kawanishi, Toshimasa, and Yuko Sueda. "Ultraviolet Protection by Beach Shade." In ASME 2008 27th International Conference on Offshore Mechanics and Arctic Engineering. ASMEDC, 2008. http://dx.doi.org/10.1115/omae2008-57287.
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Ultraviolet radiation is divided into UV-A (320–400nm), UV-B (290–320nm), UV-C (under 290nm). Of these, UV-B may be cause serious health problem, such as cataracts, loss of skin immunity, and increase of skin cancer. For this reason, it is important to know how to protect human body against the UV-B radiation. Beach shade is very effective to prevent the radiation. The radiation enters to the shade from sun and sky. The first step is to measure the sky radiance distribution of sun and sky radiation spectrum. We calculate erythema action radiation from the radiation spectrum. Sunburn chart is made using distribution of the erythema action ultraviolet radiation. Using the Sunburn chart, the shade is designed for protect against the UV radiation.
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Maabreh, Majdi, Basheer Qolomany, James Springstead, Izzat Alsmadi, and Ajay Gupta. "Deep vs. shallow learning-based filters of MS/MS spectra in support of protein search engines." In 2017 IEEE International Conference on Bioinformatics and Biomedicine (BIBM). IEEE, 2017. http://dx.doi.org/10.1109/bibm.2017.8217824.
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Cui Yan, Yao Wen, Luo Jinzhao, and Bai Jingjing. "PROTEUS-based simulation platform to study the photovoltaic cell model under partially shaded conditions." In 2011 International Conference on Electric Information and Control Engineering (ICEICE). IEEE, 2011. http://dx.doi.org/10.1109/iceice.2011.5778259.
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Gudmestad, Ove T., Arne Gürtner, and Ada Rpetto Llamazares. "Protection Barrier for Shallow Arctic Waters." In SNAME 8th International Conference and Exhibition on Performance of Ships and Structures in Ice. SNAME, 2008. http://dx.doi.org/10.5957/icetech-2008-117.
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Hydrocarbon discoveries in the shallow waters of the Northern Caspian Sea have caused intensive drilling activities to be carried out to explore the potentials. Experience with mobile drilling units in the seasonally ice infested waters hitherto originates from the drilling campaigns of the Sunkar drilling barge at Kashagan and Kalamkas. However, with increased drilling activities upcoming, innovative drilling concepts are desirable due to the objective of maintaining drilling operations (of production wells) also during the ice period with the use of conventional non-ice-resistant drilling platforms. The employment of external Shoulder Ice Barriers (SIBs) to protect a conventional jack-up drilling rig from the hazards of drifting ice in shallow water is discussed. Model tests on the SIB were performed in the large ice tank of the Hamburg Ship Model Basin (HSVA) during July 2007. These tests were performed to investigate the conceptual design under ice impact. The characteristic shoulder sections' inclination was varied to investigate the shoulder’s contribution towards stabilizing broken ice and to prevent ice from over-riding. Ice up-riding onto the barrier contributes towards increased vertical forces. The global vertical forces showed to be higher than the global horizontal forces, and in particular when ice grounding was observed. Even under extreme rubble heights of up to 9.4 m (full scale), ice overtopping the structure was effectively prevented. The SIB showed the potential to be utilized as ice protection structure for future shallow water developments. Finally, the stability on the sea bottom was investigated. The conclusion being that the concept will perform well on average to strong soils but needs to have a larger foot print area in very soft soils condition. This paper thus documents, on a feasibility level, the concept of ice protection in shallow water by means of the SIB. This paper presents a summary study of the design and verification work performed with regard to the feasibility of an innovative design.
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MattaraChalill, Subin, Chinnapalaniandi Periasamy, Pillai Nandakumar, and Ram Karthikeyan. "Interpretation and Analysis About Energy Savings in Commercial Green Houses Using Custom-Made Shadenets As Well As Thermal Reflective Screens." In ASME 2017 International Mechanical Engineering Congress and Exposition. American Society of Mechanical Engineers, 2017. http://dx.doi.org/10.1115/imece2017-71560.
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Greenhouses are known to be the modern outlook for the agronomical industry in terms of high-end yield especially in the regions where climatic conditions are not stable like in the Middle East, Europe, and United States. Crop optimization is one of the major challenges facing the farmers and the controlled production centers can dictate this difficulty in the upcoming market. Greenhouses are considered as the high -tech production centers which can support the food industry to have a green revolution through the mass production of the vegetables and spices. Properly designed commercial greenhouses can increase the yield by minimizing the operational cost especially in terms of reducing the energy consumption. In order to have a properly designed greenhouse, the selection or up gradation of the shade structures can play a vital role. Conventional greenhouses are made of polycarbonate sheets and in some cases the polyhouses by using simple polyethylene sheets. In this scenario, the main drawbacks were the energy consumption, operational expenses and the effectiveness of the indoor temperature control. Custom designed shades based on the crop requirements can provide high production rate by reducing the energy consumption. The detailed microstructural analysis in conjunction with the photosynthesis demand can provide a better selection of the shade-net or curtains. Greenhouse shade structure can be upgraded using the motorized specially designed nets or by using thermal-reflective screens. This up gradation can provide four stage advantages. In stage one this can decrease the 50% of heat energy and which will save the HVAC operational cost. During the stage, two better temperature control during the day and night will provide a good environment to provide proper PAR (Photosynthetically Active Radiation)[5] for photosynthesis, in the wavelength range of 400 to 700 nanometer. Third and fourth stages are the protection from the frost as well heat stress during the different climatic conditions. In the present market condition, the commercial greenhouses are being built in large scale by neglecting the energy saving options in shade structures. The commercial greenhouses using the upgraded shade structures can save the operational cost by 25 to 30%. Selection of this shade-nets or curtains can be done using the detailed microstructural analysis of the material. Shade-nets/curtains can be controlled manually, mechanically or can be automated in large-scale greenhouses. Flowering dates in the plants can be accelerated using the shading materials and delayed by the use of control treatment, which coincides with the results obtained in the previous studies [1]. This has proven with high land experiments [2]. Greenhouse shade nets are used in order to protect crops and plants from adverse weather conditions, animals and pests, besides providing suitable conditions for plant growth. The essential performance properties required for greenhouse shade nets are the resistance to solar radiation and weathering. The intensity of the Photo Synthetically Active Radiation (PAR) directly influences plant growth. Other nonvisible radiations are ultraviolet (UV), infrared (IR) and far infrared (FIR)[16]. Polypropylene and polyester are more resistant to UV radiation than polyethylene, which is resistant to radiations in the visible region. The use of greenhouse shade nets in outdoor conditions also requires them to be resistant to abrasion[3]. The objective of the present work is to examine the effectiveness of the properly selected shade-net/curtain in commercial greenhouses in terms of high yield energy savings. This study was conducted to compare the traditional polycarbonate sheet with the innovation of properly designed shade curtain made-up from high-density polyethylene (HDPE) fiber reinforced material discover the best shading method for plant growth in an ideal energy conservation scenario. The study was conducted in the two identical greenhouses (planted with lettuce crop) located in Al Khawaneej farm in the Emirate of Dubai in the United Arab Emirates. Yield versus the energy consumption has been observed in a period of time and obtained the reduction in energy consummation of almost 20 to 30 %.
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Engler, Adam J. "Probing Mechanisms of Mechano-Sensitive Differentiation in Mesenchymal Stem Cells." In ASME 2010 Summer Bioengineering Conference. American Society of Mechanical Engineers, 2010. http://dx.doi.org/10.1115/sbc2010-19184.
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Adult mesenchymal stem cells (MSCs) have recently been shown to be responsive to the properties of their adjacent extracellular niche, most notably physical parameters such as topography and elasticity. Elasticity varies dramatically between tissues that MSCs inhibit, which drives elasticity-based differentiation into neurons, muscle, bone, etc. However within tissues, distinct elasticity gradients, brought on by pathological conditions, e.g. myocardial infarction ∼ 8.67 ± 1.50 kPa/mm, or through normal tissue variation, e.g. 0.58 ± 0.88 kPa/mm, could drive MSC migration. In fact, MSCs appear to undergo directed migration up elasticity gradients, or “durotax,” as shallow as 0.96 kPa/mm, indicating a ‘differentiation hierarchy’ since when given the choice, MSCs will durotax into the stiffest regions of the niche and then differentiate based on niche elasticity. As cells move up the gradient, they do so by deforming their niche to determine it’s elasticity, but the molecular mechanism that converts this biophysical signal into a biochemical one which the nucleus can interpret is yet unresolved. We have identified several focal adhesion-related proteins may be capable of force-induced conformational changes, e.g. vinculin. Upon the application of different amounts of traction stress in situ by MSCs, an appropriate amount of stretching results in the exposure of cryptic MAPK binding sites within vinculin and suggests that vinculin, among other focal adhesion proteins, may be sensitive to physical ECM properties and thus able to relay information leading to differentiation of stem cells.
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McEvoy, Paul, Seojin Kim, and Malak Haynes. "Fibre Spring Mooring Solution for Mooring Floating Offshore Wind Turbines in Shallow Water." In ASME 2021 40th International Conference on Ocean, Offshore and Arctic Engineering. American Society of Mechanical Engineers, 2021. http://dx.doi.org/10.1115/omae2021-62892.
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Abstract Mooring of Floating Offshore Wind Turbines (FOWT) in shallow water sites (30–80m) is challenging. These sites account for a significant proportion of the nearer to shore potential wind farm locations, and are desirable as they are closer to existing infrastructure and easier to access. Mooring large floating structures in very shallow waters however results in very long heavy mooring lines designed to minimize platform surge and protect the electrical cables. This paper presents an innovative Fibre Spring Mooring (FSM) solution which combines a high modulus, non-stretch, lightweight rope with a compliant nonlinear polymer spring offering a complete semi-taut mooring system which can be connected directly between the platform and the seabed. The paper will present Orcaflex simulation results of a 12MW barge type FOWT platform, moored using a semi-taut FSM mooring at three chosen North Sea locations close to existing wind farms, of 30m, 40m and 50m water depths. Different FSM configurations, with different line lengths, footprint, and ratio of fibre to spring are considered.
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Gu¨rtner, Arne, Ove Tobias Gudmestad, Alf To̸rum, and Sveinung Lo̸set. "Innovative Ice Protection for Shallow Water Drilling: Part I — Presentation of the Concept." In 25th International Conference on Offshore Mechanics and Arctic Engineering. ASMEDC, 2006. http://dx.doi.org/10.1115/omae2006-92181.
Full textAbstract:
Recent discoveries of hydrocarbons in the shallow waters of the Northern Caspian Sea arise the need for intensive drilling activities to be carried out in the near future in order to explore the potentials. Experience with mobile drilling units in the seasonally ice infested waters solely originates from the current drilling campaign of the Sunkar drilling barge at Kashagan and Kalamkas. However, with increased drilling activities upcoming, innovative drilling concepts are desirable due to the objective of maintaining drilling operations during the ice period with conventional non-ice-resistant drilling platforms. Hence, this paper suggests the employment of external Shoulder Ice Barriers (SIBs) to protect a conventional jack-up drilling rig from the hazards of drifting ice in shallow water. The SIB’s design is suggested to increase the ice rubble generation at the ice facing slope and thereby provide sufficient protection from drifting ice impacts. The modular concept of the SIB makes it possible to deploy each module in a floating mode to site, whereupon they are ballasted and connected to each other, forming a sheltered position for the jack-up. Subsequent to the termination of the drilling campaign the SIB modules may be retrieved by de-ballasting and tow out, without having significant impact on the environment. This paper presents, on a technical feasible level, the concept of ice protection in shallow water by means of SIBs.
Reports on the topic "Shadow protein"
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Meir, Shimon, Michael S. Reid, Cai-Zhong Jiang, Amnon Lers, and Sonia Philosoph-Hadas. Molecular Studies of Postharvest Leaf and Flower Senescence. United States Department of Agriculture, January 2011. http://dx.doi.org/10.32747/2011.7592657.bard.
Full textAbstract:
Original objectives: To understand the regulation of abscission by exploring the nature of changes of auxin-related gene expression in tomato (Lycopersicon esculatumMill) abscission zones (AZs) following organ removal, and by analyzing the function of these genes. Our specific goals were: 1) To complete the microarray analyses in tomato flower and leaf AZs, for identifying genes whose expression changes early in response to auxin depletion; 2) To examine, using virus-induced gene silencing (VIGS), the effect of silencing target genes on ethylene sensitivity and abscission competence of the leaf and flower AZs; 3) To isolate and characterize promoters from AZ-specific genes to be used in functional analysis; 4) To generate stable transgenic tomato plants with selected genes silenced with RNAi, under the control of an AZ-specific promoter, for further characterization of their abscission phenotypes. Background: Abscission, the separation of organs from the parent plant, results in postharvest quality loss in many ornamentals and other fresh produce. The process is initiated by changes in the auxin gradient across the AZ, and is triggered by ethylene. Although changes in gene expression have been correlated with the ethylene-mediated execution of abscission, there is almost no information on the initiation of the abscission process, as the AZ becomes sensitized to ethylene. The present project was focused on elucidating these early molecular regulatory events, in order to gain a better control of the abscission process for agricultural manipulations. Major conclusions, solutions, achievements: Microarray analyses, using the Affymetrix Tomato GeneChip®, revealed changes in expression, occurring early in abscission, of many genes with possible regulatory functions. These included a range of auxin- and ethylene-related transcription factors (TFs), other TFs that are transiently induced just after flower removal, and a set of novel AZ-specific genes. We also identified four different defense-related genes, including: Cysteine-type endopeptidase, α- DOX1, WIN2, and SDF2, that are newly-associated with the late stage of the abscission process. This supports the activation of different defense responses and strategies at the late abscission stages, which may enable efficient protection of the exposed tissue toward different environmental stresses. To facilitate functional studies we implemented an efficient VIGS system in tomato, and isolated two abscission-specific promoters (pTAPG1 and pTAPG4) for gene silencing in stable transformation. Using the VIGS system we could demonstrate the importance of TAPGs in abscission of tomato leaf petioles, and evaluated the importance of more than 45 genes in abscission. Among them we identified few critical genes involved in leaf and flower abscission. These included: PTRP-F1, PRP, TKN4, KNOTTED-like homeobox TF, KD1, and KNOX-like homeodomain protein genes, the silencing of which caused a striking retardation of pedicel abscission, and ERF1, ERF4, Clavata-like3 protein, Sucrose transporter protein, and IAA10 genes, the silencing of which delayed petiole abscission. The importance of PRPand KD1 genes in abscission was confirmed also by antisense–silencing using pTAPG4. Experiments testing the effects of RNAi silencing of few other genes are still in progress, The analysis of the microarray results of flower and leaf AZs allowed us to establish a clear sequence of events occurring during acquisition of tissue sensitivity to ethylene, and to confirm our hypothesis that acquisition of ethylene sensitivity in the AZ is associated with altered expression of auxin-regulated genes in both AZs. Implication, both scientific and agricultural: Our studies had provided new insights into the regulation of the abscission process, and shaded light on the molecular mechanisms that drive the acquisition of abscission competence in the AZ. We pointed out some critical genes involved in regulation of abscission, and further expanded our knowledge of auxin-ethylene cross talk during the abscission process. This permits the development of novel techniques for manipulating abscission, and thereby improving the postharvest performance of ornamentals and other crops.
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Eneroth, Hanna, Hanna Karlsson Potter, and Elin Röös. Environmental impact of coffee, tea and cocoa – data collection for a consumer guide for plant-based foods. Department of Energy and Technology, Swedish University of Agricultural Sciences, 2022. http://dx.doi.org/10.54612/a.2n3m2d2pjl.
Full textAbstract:
In 2020, WWF launched a consumer guide on plant-based products targeting Swedish consumers. The development of the guide is described in a journal paper (Karlsson Potter & Röös, 2021) and the environmental impact of different plant based foods was published in a report (Karlsson Potter, Lundmark, & Röös, 2020). This report was prepared for WWF Sweden to provide scientific background information for complementing the consumer guide with information on coffee, tea and cocoa. This report includes quantitative estimations for several environmental categories (climate, land use, biodiversity and water use) of coffee (per L), tea (per L) and cocoa powder (per kg), building on the previously established methodology for the consumer guide. In addition, scenarios of consumption of coffee, tea and cocoa drink with milk/plant-based drinks and waste at household level, are presented. Tea, coffee and cacao beans have a lot in common. They are tropical perennial crops traditionally grown in the shade among other species, i.e. in agroforestry systems. Today, the production in intensive monocultures has negative impact on biodiversity. Re-introducing agroforestry practices may be part of the solution to improve biodiversity in these landscapes. Climate change will likely, due to changes in temperature, extreme weather events and increases in pests and disease, alter the areas where these crops can be grown in the future. A relatively high ratio of the global land used for coffee, tea and cocoa is certified according to sustainability standards, compared to other crops. Although research on the implications of voluntary standards on different outcomes is inconclusive, the literature supports that certifications have a role in incentivizing more sustainable farming. Coffee, tea and cocoa all contain caffeine and have a high content of bioactive compounds such as antioxidants, and they have all been associated with positive health outcomes. While there is a strong coffee culture in Sweden and coffee contributes substantially to the environmental impact of our diet, tea is a less consumed beverage. Cocoa powder is consumed as a beverage, but substantial amounts of our cocoa consumption is in the form of chocolate. Roasted ground coffee on the Swedish market had a climate impact of 4.0 kg CO2e per kg powder, while the climate impact of instant coffee powder was 11.5 kg CO2e per kg. Per litre, including the energy use for making the coffee, the total climate impact was estimated to 0.25 kg CO2e per L brewed coffee and 0.16 kg CO2e per L for instant coffee. Less green coffee beans are needed to produce the same amount of ready to drink coffee from instant coffee than from brewed coffee. Tea had a climate impact of approximately 6.3 kg CO2 e per kg dry leaves corresponding to an impact of 0.064 CO2e per L ready to drink tea. In the assessment of climate impact per cup, tea had the lowest impact with 0.013 kg CO2e, followed by black instant coffee (0.024 kg CO2e), black coffee (0.038 kg CO2e), and cocoa drink made with milk (0.33 kg CO2e). The climate impact of 1kg cocoa powder on the Swedish market was estimated to 2.8 kg CO2e. Adding milk to coffee or tea increases the climate impact substantially. The literature describes a high proportion of the total climate impact of coffee from the consumer stage due to the electricity used by the coffee machine. However, with the Nordic low-carbon energy mix, the brewing and heating of water and milk contributes to only a minor part of the climate impact of coffee. As in previous research, coffee also had a higher land use, water use and biodiversity impact than tea per L beverage. Another factor of interest at the consumer stage is the waste of prepared coffee. Waste of prepared coffee contributes to climate impact through the additional production costs and electricity for preparation, even though the latter was small in our calculations. The waste of coffee and tea at Summary household level is extensive and measures to reduce the amount of wasted coffee and tea could reduce the environmental impact of Swedish hot drink consumption. For the final evaluation of coffee and tea for the consumer guide, the boundary for the fruit and vegetable group was used. The functional unit for coffee and tea was 1 L prepared beverage without any added milk or sweetener. In the guide, the final evaluation of conventionally grown coffee is that it is ‘yellow’ (‘Consume sometimes’), and for organic produce, ‘light green’ (‘Please consume). The evaluation of conventionally grown tea is that it is ‘light green’, and for organic produce, ‘dark green’ (‘Preferably consume this’). For cocoa, the functional unit is 1 kg of cocoa powder and the boundary was taken from the protein group. The final evaluation of conventionally grown cocoa is that it is ‘orange’ (‘Be careful’), and for organically produced cocoa, ‘light green’.