Academic literature on the topic 'Fic Proteins'

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Journal articles on the topic "Fic Proteins"

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Li, Qinghong, Yue Sun, and Sven C. D. van IJzendoorn. "A Link between Intrahepatic Cholestasis and Genetic Variations in Intracellular Trafficking Regulators." Biology 10, no. 2 (February 4, 2021): 119. http://dx.doi.org/10.3390/biology10020119.

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Intrahepatic cholestasis is characterized by the accumulation of compounds in the serum that are normally secreted by hepatocytes into the bile. Genes associated with familial intrahepatic cholestasis (FIC) include ATP8B1 (FIC1), ABCB11 (FIC2), ABCB4 (FIC3), TJP2 (FIC4), NR1H4 (FIC5) and MYO5B (FIC6). With advanced genome sequencing methodologies, additional mutated genes are rapidly identified in patients presenting with idiopathic FIC. Notably, several of these genes, VPS33B, VIPAS39, SCYL1, and AP1S1, together with MYO5B, are functionally associated with recycling endosomes and/or the Golgi apparatus. These are components of a complex process that controls the sorting and trafficking of proteins, including those involved in bile secretion. These gene variants therefore suggest that defects in intracellular trafficking take a prominent place in FIC. Here we review these FIC-associated trafficking genes and their variants, their contribution to biliary transporter and canalicular protein trafficking, and, when perturbed, to cholestatic liver disease. Published variants for each of these genes have been summarized in table format, providing a convenient reference for those who work in the intrahepatic cholestasis field.
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Molloy, Sheilagh. "Controlling Fic proteins." Nature Reviews Microbiology 10, no. 3 (February 13, 2012): 160. http://dx.doi.org/10.1038/nrmicro2757.

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Welner, Ditte, Emil Dedic, Hans van Leeuwen, Ed Kuijper, Rene Jorgensen, Jorgensen, and Rene Jorgensen. "Structural characterisation of a Fic protein from Clostridium difficile." Acta Crystallographica Section A Foundations and Advances 70, a1 (August 5, 2014): C814. http://dx.doi.org/10.1107/s2053273314091852.

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Fic domains in proteins are found in abundance in nature from the simplest prokaryotes to animals. Interestingly, Fic domains found in two virulence factors of gram-negative bacteria have recently been demonstrated to catalyse the transfer of an AMP moiety from ATP to small host GTPases (1,2). This post-translational modification has received considerable interest and a role for adenylylation in pathology and physiology is emerging. We have structurally characterised a newly identified Fic protein of the pathogenic gram-positive bacterium Clostridium difficile. A constitutively active inhibitory helix mutant of C. difficile Fic was purified, crystallised and data collected to 1.7 Å resolution. The structure confirms C. difficult Fic protein as an ATP binding protein and reveal a binding site similar to other confirmed virulent Fic proteins. Surprisingly, this gram-positive Fic protein does not seem to target GTPases in humans and currently target identification is being chased. The current status of the project will be presented.
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Roy, Craig R., and Jacqueline Cherfils. "Structure and function of Fic proteins." Nature Reviews Microbiology 13, no. 10 (August 24, 2015): 631–40. http://dx.doi.org/10.1038/nrmicro3520.

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Roy, C. R., and S. Mukherjee. "Bacterial FIC Proteins AMP Up Infection." Science Signaling 2, no. 62 (March 10, 2009): pe14. http://dx.doi.org/10.1126/scisignal.262pe14.

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Stanger, Frédéric V., Björn M. Burmann, Alexander Harms, Hugo Aragão, Adam Mazur, Timothy Sharpe, Christoph Dehio, Sebastian Hiller, and Tilman Schirmer. "Intrinsic regulation of FIC-domain AMP-transferases by oligomerization and automodification." Proceedings of the National Academy of Sciences 113, no. 5 (January 19, 2016): E529—E537. http://dx.doi.org/10.1073/pnas.1516930113.

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Filamentation induced by cyclic AMP (FIC)-domain enzymes catalyze adenylylation or other posttranslational modifications of target proteins to control their function. Recently, we have shown that Fic enzymes are autoinhibited by an α-helix (αinh) that partly obstructs the active site. For the single-domain class III Fic proteins, the αinh is located at the C terminus and its deletion relieves autoinhibition. However, it has remained unclear how activation occurs naturally. Here, we show by structural, biophysical, and enzymatic analyses combined with in vivo data that the class III Fic protein NmFic from Neisseria meningitidis gets autoadenylylated in cis, thereby autonomously relieving autoinhibition and thus allowing subsequent adenylylation of its target, the DNA gyrase subunit GyrB. Furthermore, we show that NmFic activation is antagonized by tetramerization. The combination of autoadenylylation and tetramerization results in nonmonotonic concentration dependence of NmFic activity and a pronounced lag phase in the progress of target adenylylation. Bioinformatic analyses indicate that this elaborate dual-control mechanism is conserved throughout class III Fic proteins.
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Heinrich, J. N., R. P. Ryseck, H. Macdonald-Bravo, and R. Bravo. "The product of a novel growth factor-activated gene, fic, is a biologically active "C-C"-type cytokine." Molecular and Cellular Biology 13, no. 4 (April 1993): 2020–30. http://dx.doi.org/10.1128/mcb.13.4.2020-2030.1993.

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We have characterized a new member of the superfamily of proinflammatory peptides encoded by a growth factor-inducible gene, fic, previously isolated by differential screening of a cDNA library of mRNA from serum-stimulated NIH 3T3 cells. Immunoprecipitation analyses showed that the protein was rapidly induced following serum stimulation and secreted unglycosylated into the medium. The fic protein, FIC, shows highest sequence homology (57%) to human and rabbit monocyte chemoattractant protein 1 (MCP-1), an established monocyte activator. To determine the biological activity of FIC and to compare it with that of mouse MCP-1 (muMCP-1), both proteins were expressed in the baculovirus system. FIC and muMCP-1 were purified to near homogeneity by a two-step chromatography protocol. Both proteins elicited changes in intracellular calcium concentration in human monocytes. The effect was dependent on external Ca2+ and was inhibited by pretreatment of cells with pertussis toxin. FIC did not desensitize human monocytes to the three related cytokines muMCP-1, human MCP-1 (huMCP-1), and huMCP-2. However, pretreatment with muMCP-1 or huMCP-1, but not with huMCP-2, desensitized human monocytes to FIC. Specific binding of [125I]FIC was found in human monocytes, mouse monocytic cultured cells, and human endothelial cells but not in lymphocytes, neutrophils, or primary mouse fibroblasts. Scatchard analysis of the binding of [125I]FIC to human monocytes showed the presence of two classes of receptors, with apparent KdS of 1.2 and 7.7 nM and receptor numbers per cell of 2,400 and 6,300, respectively. FIC, muMCP-1, and huMCP-1 competed to the same extent for the binding of [125I]FIC to human monocytes, contrary to huMCP-2, which competed very ineffectively, if at all.
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Heinrich, J. N., R. P. Ryseck, H. Macdonald-Bravo, and R. Bravo. "The product of a novel growth factor-activated gene, fic, is a biologically active "C-C"-type cytokine." Molecular and Cellular Biology 13, no. 4 (April 1993): 2020–30. http://dx.doi.org/10.1128/mcb.13.4.2020.

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We have characterized a new member of the superfamily of proinflammatory peptides encoded by a growth factor-inducible gene, fic, previously isolated by differential screening of a cDNA library of mRNA from serum-stimulated NIH 3T3 cells. Immunoprecipitation analyses showed that the protein was rapidly induced following serum stimulation and secreted unglycosylated into the medium. The fic protein, FIC, shows highest sequence homology (57%) to human and rabbit monocyte chemoattractant protein 1 (MCP-1), an established monocyte activator. To determine the biological activity of FIC and to compare it with that of mouse MCP-1 (muMCP-1), both proteins were expressed in the baculovirus system. FIC and muMCP-1 were purified to near homogeneity by a two-step chromatography protocol. Both proteins elicited changes in intracellular calcium concentration in human monocytes. The effect was dependent on external Ca2+ and was inhibited by pretreatment of cells with pertussis toxin. FIC did not desensitize human monocytes to the three related cytokines muMCP-1, human MCP-1 (huMCP-1), and huMCP-2. However, pretreatment with muMCP-1 or huMCP-1, but not with huMCP-2, desensitized human monocytes to FIC. Specific binding of [125I]FIC was found in human monocytes, mouse monocytic cultured cells, and human endothelial cells but not in lymphocytes, neutrophils, or primary mouse fibroblasts. Scatchard analysis of the binding of [125I]FIC to human monocytes showed the presence of two classes of receptors, with apparent KdS of 1.2 and 7.7 nM and receptor numbers per cell of 2,400 and 6,300, respectively. FIC, muMCP-1, and huMCP-1 competed to the same extent for the binding of [125I]FIC to human monocytes, contrary to huMCP-2, which competed very ineffectively, if at all.
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Zekarias, Bereket, Seema Mattoo, Carolyn Worby, Jason Lehmann, Ricardo F. Rosenbusch, and Lynette B. Corbeil. "Histophilus somni IbpA DR2/Fic in Virulence and Immunoprotection at the Natural Host Alveolar Epithelial Barrier." Infection and Immunity 78, no. 5 (February 22, 2010): 1850–58. http://dx.doi.org/10.1128/iai.01277-09.

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ABSTRACT Newly recognized Fic family virulence proteins may be important in many bacterial pathogens. To relate cellular mechanisms to pathogenesis and immune protection, we studied the cytotoxicity of the Histophilus somni immunoglobulin-binding protein A (IbpA) direct repeat 2 Fic domain (DR2/Fic) for natural host target cells. Live virulent IbpA-producing H. somni strain 2336, a cell-free culture supernatant (CCS) of this strain, or recombinant DR2/Fic (rDR2/Fic) caused dramatic retraction and rounding of bovine alveolar type 2 (BAT2) epithelial cells. IbpA-deficient H. somni strain 129Pt and a Fic motif His298Ala mutant rDR2/Fic protein were not cytotoxic. The cellular mechanism of DR2/Fic cytotoxicity was demonstrated by incubation of BAT2 cell lysates with strain 2336 CCS or rDR2/Fic in the presence of [α-32P]ATP, which resulted in adenylylation of Rho GTPases and cytoskeletal disruption. Since IbpA is not secreted by type III or type IV secretion systems, we determined whether DR2/Fic entered the host cytoplasm to access its Rho GTPase targets. Although H. somni did not invade BAT2 cells, DR2/Fic was internalized by cells treated with H. somni, CCS, or the rDR2/Fic protein, as shown by confocal immunomicroscopy. Transwell bacterial migration assays showed that large numbers of strain 2336 bacteria migrated between retracted BAT2 cells, but IbpA-deficient strain 129Pt did not cross a monolayer unless the monolayer was pretreated with strain 2336 CCS or rDR2/Fic protein. Antibody to rDR2/Fic or passively protective convalescent-phase serum blocked IbpA-mediated cytotoxicity and inhibited H. somni transmigration across BAT2 monolayers, confirming the role of DR2/Fic in pathogenesis and corresponding to the results for in vivo protection in previous animal studies.
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Schirmer, Tilman, Tjaart A. P. de Beer, Stefanie Tamegger, Alexander Harms, Nikolaus Dietz, David M. Dranow, Thomas E. Edwards, Peter J. Myler, Isabelle Phan, and Christoph Dehio. "Evolutionary Diversification of Host-Targeted Bartonella Effectors Proteins Derived from a Conserved FicTA Toxin-Antitoxin Module." Microorganisms 9, no. 8 (July 31, 2021): 1645. http://dx.doi.org/10.3390/microorganisms9081645.

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Proteins containing a FIC domain catalyze AMPylation and other post-translational modifications (PTMs). In bacteria, they are typically part of FicTA toxin-antitoxin modules that control conserved biochemical processes such as topoisomerase activity, but they have also repeatedly diversified into host-targeted virulence factors. Among these, Bartonella effector proteins (Beps) comprise a particularly diverse ensemble of FIC domains that subvert various host cellular functions. However, no comprehensive comparative analysis has been performed to infer molecular mechanisms underlying the biochemical and functional diversification of FIC domains in the vast Bep family. Here, we used X-ray crystallography, structural modelling, and phylogenetic analyses to unravel the expansion and diversification of Bep repertoires that evolved in parallel in three Bartonella lineages from a single ancestral FicTA toxin-antitoxin module. Our analysis is based on 99 non-redundant Bep sequences and nine crystal structures. Inferred from the conservation of the FIC signature motif that comprises the catalytic histidine and residues involved in substrate binding, about half of them represent AMP transferases. A quarter of Beps show a glutamate in a strategic position in the putative substrate binding pocket that would interfere with triphosphate-nucleotide binding but may allow binding of an AMPylated target for deAMPylation or another substrate to catalyze a distinct PTM. The β-hairpin flap that registers the modifiable target segment to the active site exhibits remarkable structural variability. The corresponding sequences form few well-defined groups that may recognize distinct target proteins. The binding of Beps to promiscuous FicA antitoxins is well conserved, indicating a role of the antitoxin to inhibit enzymatic activity or to serve as a chaperone for the FIC domain before translocation of the Bep into host cells. Taken together, our analysis indicates a remarkable functional plasticity of Beps that is mostly brought about by structural changes in the substrate pocket and the target dock. These findings may guide future structure–function analyses of the highly versatile FIC domains.
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Dissertations / Theses on the topic "Fic Proteins"

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Al, Madadha Mohammad Emad. "Functional analysis of Fic domain bearing proteins in Klebsiella pneumoniae." Thesis, University of Leicester, 2017. http://hdl.handle.net/2381/39871.

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Fic domain bearing proteins are characterized with the presence of a domain carrying the conserved amino acid sequence (HPFX(D/E)GNGR). These proteins are present in all walks of life but are more concentrated within prokaryotes and more so within bacteria. In recent years these proteins have been increasingly characterized and their role in bacterial virulence is being elucidated. Fic proteins are usually secreted by bacteria and once delivered into the host cell they usually target cytoskeleton regulating G proteins that affect the target host in different ways depending on the target G protein. In Klebsiella pneumoniae, we have identified 5 homologous genes that code for five different Fic domain bearing proteins in this bacteria. Our first effort was to determine if these proteins were secreted, to verify if they adhere to the toxin-secretion system paradigm. The work then focused on determining the virulence effect of these proteins in an in vivo assay, an in vitro assay and an enzymatic assay for the Fic-RL protein. Fic- RL is one of the five proteins in K. pneumoniae have been shown to be conserved in all 80 sequenced strains of this bacteria. In our secretion assay this protein have been shown to be secreted by the bacteria, moreover, by utilizing different mutants that lacked different parts of secretion systems, we have been able to determine that the T4SS present on the Integrative and Conjugative Element 1 (icekp1) to be responsible for the secretion of this protein and not the other 4 homologs. Virulence assays showed that when this protein was expressed with eukaryotic cells by means of transfection, confocal and fluorescent microscopy revealed that cytotoxic effect are evident as cell rounding and actin cytoskeletal collapse in transfected cells, which does not occur when a mutated version of the protein is instead expressed. Survival killing assays utilizing the larvae of the Galleria mellonella wax moth, revealed significant attenuation of strains lacking the gene coding for Fic domain bearing proteins, which is partially complemented by re-introducing the genes in plasmid constructs. The enzymatic function for the Fic-RL protein was shown in a Guanine Exchange Factor assay, designed to reveal if a protein is able to utilize fluorophore bound substrates in its reaction of provided G protein targets (Cdc42, Rac1, RhoA), showed that Fic-RL is able to cause an increase in relative fluorescence measured that was similar to a known Guanine Exchange Factor (hDbs) but only when used on Cdc42 and not the other two G proteins.
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Veyron, Simon. "Structure et fonction des toxines bactériennes à domaine FIC." Thesis, Université Paris-Saclay (ComUE), 2017. http://www.theses.fr/2017SACLS452/document.

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Les protéines à domaine FIC (Filamentation induced by cAMP) sont très répandues chez les bactéries où elles catalysent l’ajout d’une modification post-traductionnelle contenant un phosphate à une protéine cible, en utilisant différents co-substrats comme l’ATP. Certaines de ces protéines sont des toxines sécrétées par des pathogènes humains, mais la fonction de la plupart d’entre elles reste mystérieuse. Plus d’une dizaine de structures de protéines FIC ont été déterminées récemment, qui ont permis d’élucider leur mécanisme catalytique. L’une des sous-familles de protéines FIC possède un glutamate dans leur site catalytique, dont il a été proposé qu’il aurait une fonction auto-inhibitrice pour la fixation de l’ATP. Durant ma thèse, j’ai étudié la structure et les mécanismes de régulation de deux familles de protéines FIC : les protéines FIC à glutamate inhibiteur, et la toxine AnkX de la bactérie pathogène Legionella pneumophila.La première étude s’est intéressée à la protéine FIC de la bactérie pathogène Enterococcus faecalis (EfFIC), qui fait partie de la sous-famille des protéines FIC possédant un glutamate inhibiteur. J’ai résolu plusieurs structures cristallographique d’EfFIC, qui ont permis de caractériser son site catalytique et comment elle fixe l’AMP et l’ADP. En utilisant une propriété fréquemment observée d’auto-AMPylation (modification par l’AMP), j’ai montré au moyen d’ATP radioactif qu’EfFIC possède une activité basale d’auto-AMPylation, et j’ai identifié une nouvelle activité de dé-AMPylation. En m’inspirant des métaux observés dans mes structures cristallographiques, j’ai montré que l’alternance entre les activités d’AMPylation et de de-AMPylation dépend de la nature du métal fixé dans le site actif et de la présence du glutamate. Ce glutamate régulateur est également présent chez une protéine humaine, HYPE, qui possède une double activité d’AMPylation et dé-AMPylation d’ une chaperone du réticulum endoplasmique. Par un test de fluorescence, j’ai enfin montré que l’activité de HYPE était elle aussi régulée par les métaux comme celle de EfFIC. Ces résultats suggèrent un nouveau modèle de régulation partagé par des protéines FIC de la bactérie à l’homme.La seconde étude a porté sur la toxine AnkX de Legionella pneumophila, qui modifie les petites protéines G de la famille de Rab Rab1 et Rab35 (régulatrices du trafic cellulaire) par une molécule de phosphocholine (PC). En utilisant des liposomes de composition contrôlée, j’ai montré qu’AnkX interagit avec les membranes, et j’ai identifié par mutagenèse son domaine d’interaction avec les membranes. Au moyen de petites GTPases Rab ancrées artificiellement à la surface de liposomes par une queue 6his remplaçant le lipide naturel, j’ai montré que l’activité d’AnkX est stimulée par la présence de membranes. Des résultats préliminaires suggérent que Rab35 est un meilleur substrat que Rab1a, ce qui pourrait renseigner sur la fonction et le compartiment cellulaire où se trouve la toxine. J’ai ensuite mené une étude structurale d’AnkX par diffusion des rayons X aux petits angles (SAXS), qui permet d’obtenir des informations structurales en solution. AnkX est constitué d’un domaine FIC, de répétitions ankyrine et d’un domaine C-terminal. L’analyse en SAXS montre que ces domaines s’organisent en forme de fer à cheval, suggérant un modèle d’association bi-partite du complexe AnkX/Rab aux membranes. L’ensemble de ces résultats conduit à un modèle dans lequel l’activité d’AnkX est régulée spatialement par les membranes, ce qui pourrait lui permettre de cibler à la fois les petites GTPases Rab cellulaires et le compartiment membranaire
FIC (Filamentation induced by cAMP ) domain containing proteins are widespread in bacteria where they use different substrate such ATP to modify a target protein with a phosphate containing post-translational modification. Some of those proteins are secreted toxins from pathogens but the function of the majority stay unknown. Some recently resolved structures explain the catalytic mechanism. A subfamily of FIC proteins was proposed to be auto-inhibited for ATP binding by a glutamate in their active site. In my thesis, I lead a structural and biochemical study of two FIC proteins family: the auto-inhibited by a glutamate FIC proteins and the Legionella pneumophila toxin AnkX.For the first study, I focused on the pathogenic bacteria Enterococcus faecalis protein EfFIC that is an auto-inhibited FIC protein. I solved several crystallographic structures to characterize the active site and the AMP and ADP binding. Using the classic auto-AMPylation (modification with an AMP molecule) mechanism and radioactive ATP, I showed that EfFIC is active and I identified a new de-AMPylation activity. Using metals found in my crystallographic structures, I showed that the AMPylation and de-AMPylation switch is controlled by the nature of the metal bound in the active site and that this switch is inhibitory glutamate-dependent. This glutamate is found in human HYPE that shows a double AMPyaltion and de-AMPylation activity of the ER chaperone BIP. Using fluorescence assays, I showed that those two activities are alors regulated by metals as in EfFIC. Those results point on a new regulation model shared between FIC proteins from bacteria to human.The second study focused on Legionella pneumophila toxin AnkX that modifies small GTPases Rab1 and Rab35 with a phosphocholine (PC) molecule. Using controlled composition liposomes, I showed that AnkX interact with membranes and mapped the interaction domain by mutagenesis. With artificially anchored to nickel containing liposomes surface Rab GTPases, I demonstrated the stimulation of AnkX activity by the membranes. Preliminary results also suggest that Rab35 is a better substrate than Rab1a, giving information on AnkX function and localization during infection. I lead a small angle X-ray scattering (SAXS) study on AnkX that gave low-resolution structural information on AnkX in solution. The analyses of SAXS results show that AnkX is horseshoe shaped, suggesting an association with the membrane and Rab of AnkX model. In this model, membranes spatially regulate AnkX, allowing a targeting of Rab and cellular compartment targeting
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Govers-Riemslag, Josepha Wilhelmina Philomena. "Protein-protein and protein-membrane interactions in prothrombin activation." Maastricht : Maastricht : Rijksuniversiteit Limburg ; University Library, Maastricht University [Host], 1994. http://arno.unimaas.nl/show.cgi?fid=6949.

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Barriga, Montero Marissa Cecilia, Iwamoto Almendra Mayumi Ordaya, Loayza Raúl Anibal Jesús Pinto, Osorio Mauricio Roca, and Llamosas Mirella Alison Zevallos. "Kallmi Fit." Bachelor's thesis, Universidad Peruana de Ciencias Aplicadas (UPC), 2020. http://hdl.handle.net/10757/654683.

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El presente trabajo tiene como objetivo principal la elaboración y planificación correspondiente de las diferentes tareas y actividades base para iniciar la producción y comercialización de un complemento proteico en polvo especializado para cada deporte o carga física correspondiente, asimismo, será la de comprobar que la idea de negocio es rentable. Actualmente, se pueden encontrar diferentes complementos proteicos en polvo de diferentes marcas con beneficios relativamente similares. El objetivo de estos se basa en la mejoría del estado físico del individuo quien las consume. Sin embargo, se puede apreciar que estas proteínas contienen una composición regular. Por lo que, su composición no se adecua a diferentes cantidades de ejercicio o cargas físicas. Por este motivo, nuestro producto tiene como objetivo principal adecuarse a las diferentes cantidades de carga física de los diferentes tipos de consumidores, clasificándose en deportes o actividades de bajo consumo calórico como de alto consumo calórico de igual manera. Cabe mencionar, que nuestro producto está dirigido a hombres y mujeres cuyo rango de edad se encuentre entre los 18 a 45 años y que hagan deporte regularmente. Para demostrar que la idea de negocio será rentable, se realizaron diferentes análisis de factores internos y externos que pudieran beneficiar o perjudicar a nuestro proyecto. En adición a esto, se realizó el cálculo del valor actual neto proyectado del negocio para comprobar que este generará ganancias en el futuro.
The main objective of the present work is the elaboration and corresponding planning of the different tasks and activities that are the base to start the production and commercialization of a specialized protein powder supplement for each sport or corresponding physical load, as well as to demonstrate that the business idea is profitable. Nowadays, we can find different protein powder supplements from different brands with relatively similar benefits. This objective is based on the improvement of the physical state of the individual who consumes them. However, we can appreciate that these proteins contain a regular composition. Thus, their composition is not adapted to different amounts of exercise or physical loads. For this reason, our product has, as the main objective, to adapt to the different amounts of physical load of the different consumers, being classified in sports or activities of low caloric consumption as of high caloric consumption in the same way. It is worth mentioning that our product is aimed at those men and women whose age is between 18 and 45 years old and who do sports regularly. In order to demonstrate that our business idea will be profitable, different analyses of internal and external factors that could benefit or harm our project were carried out. In addition, we calculated the projected net present value of the business, to prove that it will generate profits in the future.
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Sarti, Edoardo. "Assessing the structure of proteins and protein complexes through physical and statistical approaches." Doctoral thesis, SISSA, 2015. http://hdl.handle.net/20.500.11767/4863.

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Determining the correct state of a protein or a protein complex is of paramount importance for current medical and pharmaceutical research. The stable conformation of such systems depend on two processes called protein folding and protein-protein interaction. In the course of the last 50 years, both processes have been fruitfully studied. Yet, a complete understanding is still not reached, and the accuracy and the efficiency of the approaches for studying these problems is not yet optimal. This thesis is devoted to devising physical and statistical methods for recognizing the native state of a protein or a protein complex. The studies will be mostly based on BACH, a knowledge-based potential originally designed for the discrimination of native structures in protein folding problems. BACH method will be analyzed and extended: first, a new method to account for protein-solvent interaction will be presented. Then, we will describe an extension of BACH aimed at assessing the quality of protein complexes in protein-protein interaction problems. Finally, we will present a procedure aimed at predicting the structure of a complex based on a hierarchy of approaches ranging from rigid docking up to molecular dynamics in explicit solvent. The reliability of the approaches we propose will be always benchmarked against a selection of other state-of-the-art scoring functions which obtained good results in CASP and CAPRI competitions.
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Schellings, Marcus Wilhelmus Maria. "Matricellular proteins essential modulators of cardiac remodeling /." Maastricht : Maastricht : Universiteit Maastricht ; University Library, Universiteit Maastricht [host], 2007. http://arno.unimaas.nl/show.cgi?fid=9446.

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Ficz, Gabriella. "Protein dynamics in the nucleus implications for gene expression /." Doctoral thesis, [S.l.] : [s.n.], 2005. http://webdoc.sub.gwdg.de/diss/2005/ficz.

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PACHETTI, MARIA. "Studio UV Raman Risonante sulla struttura proteica, sulla fibrillazione e sull'interazione proteina-ligando." Doctoral thesis, Università degli Studi di Trieste, 2021. http://hdl.handle.net/11368/2988326.

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Il termine "proteinopatia" è stato coniato per indicare una classe di disturbi legati al mal ripiegamento delle proteine come le malattie di Alzheimer (AD) e Parkinson (PD). Oggi, le demenze, l'AD e il diabete di tipo II sono considerati tra le prime 20 cause di morte in tutto il mondo dall'Organizzazione Mondiale della Sanità (OMS). Il mal-ripiegamento non solo induce la perdita delle funzioni biologiche delle proteine, ma promuove anche un processo termodinamicamente favorito chiamato "aggregazione", che generalmente termina con la formazione di fibrille proteiche, cioè una struttura filiforme ordinata fatta di proteine mal ripiegate. La formazione di specie proteiche non native e la formazione di depositi di fibrille all'interno o all'esterno delle cellule potrebbero compromettere le funzioni biologiche native di cellule, tessuti e organi. Nonostante la spettroscopia UV Raman Risonante (UVRR) non fornisca misure ad alta risoluzione, questa offre preziose informazioni sulla struttura nativa del campione, superando così le limitazioni di cryo-EM e ssNMR. Per citare alcuni vantaggi, la spettroscopia UVRR offre la possibilità di lavorare in condizioni acquose, diluite, senza richiedere manipolazioni chimiche del campione. Ancora più importante, la spettroscopia UVRR offre la possibilità di aumentare selettivamente la sezione d'urto Raman dei modi vibrazionali di peculiari cromofori proteici a seconda dell'energia di eccitazione scelta. Lo scopo di questa tesi di dottorato è quello di mostrare l'utilità della spettroscopia UVRR per l'indagine strutturale delle fibrille proteiche e anche delle interazioni proteina-ligando, collegando il comportamento di diversi biomarkers spettroscopici alla modifica strutturale delle proteine durante entrambi i fenomeni. In particolare: - abbiamo dimostrato la capacità della spettroscopia UVRR di ottenere importanti informazioni sulla modifica strutturale delle proteine durante la fibrillazione e durante l'interazione con i ligandi, studiando la fibrillazione del lisozima contenuto nell'albume d'uovo di gallina (HEWL) e dell'insulina umana e la loro interazione con un antiossidante, il resveratrolo. Abbiamo fornito un solido approccio spettroscopico basato sulla spettroscopia UVRR e completato da altre classiche tecniche spettroscopiche, con l'obiettivo di tradurre questo approccio multi-tecnica verso l'indagine di una classe più interessante di proteine, cioè le proteine intrinsecamente disordinate. - abbiamo caratterizzato un nuovo meccanismo di fibrillazione della diidrofolato reduttasi (DHFR) di E.Coli, indotta a pH neutro dalla presenza di spermina. Infatti, l'interazione con la spermina induce una parziale inibizione dell'attività enzimatica, stabilizzando il DHFR in un conformatore ad alta energia. Questa struttura rimane stabile per alcuni giorni, poi inizia a precipitare in fibrille insolubili. Il meccanismo di interazione tra E.Coli DHFR e la spermina è stato discusso in questa sezione, fornendo un chiaro esempio di ligando che induce la fibrillazione. -Nell'ultima sezione, il solido protocollo basato su UVRR testato con sistemi modello, e l'identificazione di peculiari biomarcatori spettrali UVRR sensibili alla fibrillazione della proteina e all'interazione con ligandi sono stati sfruttati trattando una nota proteina intrinsecamente disordinata (IDP), che è l'α-sinucleina (aS). Abbiamo proposto un metodo alternativo di analisi degli spettri UVRR basato sull'uso di un riferimento proteico esterno per chiarire la struttura di aS e la sua forma troncata al C-terminale, (1-120) aS. Abbiamo proposto un metodo alternativo di analisi degli spettri UVRR basato sull'uso di un riferimento proteico esterno per stimare approssimativamente quanti residui Tyr sono protetti dal solvente nel caso sia delle fibrille che dei monomeri di aS, ottenendo risultati in linea con la recente letteratura.
The term “proteinopathy” was coined to indicate a class of disorders related to protein misfolding such as Alzheimer’s (AD) and Parkinson’s (PD) diseases. Nowadays, dementias, AD and type II diabetes are considered within the top 20 causes of death worldwide by World Health Organization (WHO). Misfolding not only induces the loss of proteins’ biological functions, but also promotes a thermodynamically favoured process called “aggregation”, that generally ends with the formation of protein fibrils, i.e. an ordered thread-like structure made of misfolded proteins. The formation of non-native protein species as well as the formation of fibrils deposits within or outside cells could compromise the native biological functions of cells, tissues and organs. Despite UV Resonance Raman (UVRR) spectroscopy does not offer high-structural resolution measurements, it provides valuable insights on the native-like structure of the sample, thus overcoming the limitations of cryo-EM and ssNMR. To name few advantages, UVRR spectroscopy offers the possibility to work in diluted, native-like aqueous conditions, without requiring a chemical manipulation of the sample. More importantly, UVRR spectroscopy opens the possibility to selectively enhance the Raman cross section of peculiar protein chromophore vibrational modes depending on the radiation excitation energy chosen. The aim of the this Ph.D. thesis is to show the usefulness of UV Resonance Raman (UVRR) spectroscopy for the structural investigation of protein fibrils and also of protein-ligand interactions, linking the behaviour of several spectroscopic biomarkers to the structural modification of proteins during both phenomena. In particular: - we demonstrated the ability of UVRR spectroscopy to get important insights on the structural modification of proteins upon fibrillation and upon interaction with ligands, by studying the fibrillation of hen egg white lysozyme (HEWL) and human insulin and their interaction with an antioxidant, which is resveratrol. We provide a solid spectroscopic approach based on UVRR spectroscopy and complemented by other classical spectroscopic techniques, with the aim to translate this multi-technique approach towards the investigation of a more interesting class of proteins, i.e. the intrinsically disordered proteins. - we characterized a novel mechanism of fibrillation of E.Coli dihydrofolate reductase (DHFR), induced at neutral pH by the presence of spermine. In fact, the interaction with spermine induces a partial inhibition of the enzymatic activity, stabilizing DHFR in a high energy conformer. This structure remains stable for few days, then starts to precipitate into insoluble fibrils. The mechanism of interaction between E.Coli DHFR and spermine has been discussed in this section, providing a clear example of a fibrillation-inducing ligand. -in the last section, the solid UVRR-based protocol tested with model systems, and the identification of peculiar UVRR spectral biomarkers sensitive to protein fibrillation and to interaction with ligands have been exploited dealing with a well-known intrinsically disordered protein (IDP), which is α-synuclein (aS). We proposed an alternative method of UVRR spectra analysis based on the use of an external protein reference to elucidate the structure of aS and its C-terminus truncated form, (1-120) aS. We proposed an alternative method of UVRR spectra analysis based on the use of an external protein reference roughly estimate how many Tyr residues are solvent-protected in the case of both aS fibrils and monomers, obtaining results in line with the recent literature.
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Kragten, Johannes Albertus. "New myocardial marker proteins in acute myocardial infarction quantitative aspects : release patterns of cellular enzymes and proteins in plasma following acute myocardial infarction /." Assen : Maastricht : Dekker & van de Vegt en Van Gorcum ; University Library, Maastricht University [Host], 1998. http://arno.unimaas.nl/show.cgi?fid=6052.

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Jie, Gerard Kon Siong. "The role of vitamin K-dependent proteins in tissue calcification." Maastricht : Maastricht : Universitaire Pers Maastricht ; University Library, Maastricht University [Host], 1995. http://arno.unimaas.nl/show.cgi?fid=8340.

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Books on the topic "Fic Proteins"

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Mastrianni, James A., and Joshuae G. Gallardo. Prion Diseases. Oxford University Press, 2017. http://dx.doi.org/10.1093/med/9780199937837.003.0166.

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Prion diseases are transmissible fatal neurodegenerative disorders resulting from the accumulation of misfolded prion protein. Although primarily sporadic diseases, 5% to 10% result from a mutation of the prion protein gene (PRNP), and less than 1% occur from exposure to prions. The current family of prion diseases includes Creutzfeldt-Jakob disease (CJD), Gerstmann-Sträussler-Scheinker disease (GSS), fatal insomnia (FI), variant CJD (vCJD), and variably protease-sensitive prionopathy (VPSPr). Kuru is a disease of historical interest that was transmitted through cannibalistic rituals. Iatrogenic CJD (iCJD) is the result of secondary transmission of prion disease from contaminated biologicals.
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Burton, Derek, and Margaret Burton. The skeleton, support and movement. Oxford University Press, 2017. http://dx.doi.org/10.1093/oso/9780198785552.003.0003.

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Buoyancy largely supports fish, reducing the role of the skeleton, which functions as an attachment for muscle involved in movement and in protection, as exoskeleton (scales, scutes, bony plates) and as endoskeleton (vertebral column, skull). The general organization of fish skeletons and their component parts are described, as well as bone and cartilage. The interesting occurrence of acellular bone, additional to cellular bone, in teleosts is considered. Fish show metameric segmentation with myotomes on either side of the vertebral column, the latter acting as a compression strut, preventing shortening. Myotome muscle is organized into linear units named sarcomeres which contract by means of protein fibres, myosin and actin, sliding past each other. Usually fish body wall muscles occur as a thin outer layer of aerobic red muscle, with an inner thick region of anaerobic white muscle. Interspecific variability in the relative roles of myotomes and fin musculature in swimming is discussed.
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Burin, Eric, ed. Protesting on Bended Knee: Race, Dissent and Patriotism in 21st Century America. The Digital Press at the University of North Dakota, 2018. http://dx.doi.org/10.31356/dpb013.

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Protesting on Bended Knee eyes the modern crusade for racial equality through the prism of the demonstrations associated with Colin Kaepernick, a professional football player who in 2016 began kneeling during the national anthem to draw attention to discrimination and injustice. A diverse array of thirty-one authors explain in brief essays what they see in the protests; collectively, they describe where the demonstrations fit within Americans’ quest to form “a more perfect union”; the legal landscape of dissent; the revival of athlete-activists; the tactics of protesters and counter-tactics of their opponents; and the perspective of others—reporters, coaches, players, and fans—“in the arena.” Their observations, along with an extensive Introduction by historian Eric Burin, provide a nearly contemporaneous account of the latest chapter in a freedom struggle as old as America itself. Eric Burin is Professor of History at the University of North Dakota, and author of Slavery and the Peculiar Solution: A History of the American Colonization Society (2005) and editor of Picking the President: Understanding the Electoral College (2016).
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Bioquímica Estructural: Prácticas de laboratorio. Universidad Juárez Autónoma de Tabasco, 2021. http://dx.doi.org/10.19136/book.225.

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Este manual de prácticas de laboratorio considera el aspecto experimental del programa de estudios de la asignatura de Bioquímica Estructural de la Licenciatura en Nutrición de la Universidad Juárez Autónoma de Tabasco (UJAT). Dicha asignatura es parte del Área de formación Sustantiva Profesional, por lo que brinda los fundamentos teóricos y metodológicos para desarrollarse en el campo profesional. Las prácticas están diseñadas para realizar actividades tanto en el laboratorio como fuera de él. Su realización contribuirá a comprender las propiedades estructurales y químicas básicas de las proteínas y los glúcidos que han permitido un amplio desarrollo tecnológico. El contenido se encuentra directamente vinculado a los objetivos del programa de estudio, dando énfasis en conocer y comprender las aplicaciones en el ámbito clínico y alimentario. Por otro lado, y dado el enfoque de aprendizaje basado en competencias de las asignaturas de la Licenciatura en Nutrición de la UJAT, se ha incluido una novedosa guía de reporte de prácticas donde el alumno describe el proceso de planeación y ejecución de la práctica en tres ámbitos: individual, por equipo y grupal; con el fin de que evalúe su capacidad para: comprender los fundamentos y planear la práctica, organizarse y trabajar en equipo, comprometerse de forma individual en la práctica grupal e integrarse en el desarrollo de la práctica y el análisis de los resultados.
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Lowe, Hannah, Shuying Huang, and Nuran Urkmezturk. A UK ANALYSIS: Empowering Women of Faith in the Community, Public Service, and Media. Dialogue Society, 2022. http://dx.doi.org/10.55207/zhqg9062.

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In the UK, belief, and faith are protected under the legal frame of the Human Rights Act 1998 (HRA) and the Equality Act 2010 (Perfect 2016, 11), in which a person is given the right to hold a religion or belief and the right to change their religion or belief. It also gives them a right to show that belief as long as the display or expression does not interfere with public safety, public order, health or morals, or the rights and freedoms of others (Equality Act 2010). The Equality Act 2010 protects employees from discrimination, harassment and victimisation because of religion or belief. Religion or belief are mainly divided into religion and religious belief, and philosophical belief (Equality Act 2010, chap. 1). The Dialogue Society supports the Equality Act 2010 (Perfect 2016, 11). Consequently, The Dialogue Society believes we have a duty to eliminate discrimination, advance equality of opportunity, and foster good relations within our organisation and society. The Dialogue Society aims to promote equality and human rights by empowering people and bringing social issues to light. To this end, we have organised many projects, research, courses, scriptural reasoning readings/gatherings, and panel discussions specifically on interfaith dialogue, having open conversations around belief and religion. To encourage dialogue, interaction and cooperation between people working on interreligious dialogue and to demonstrate good interfaith relations and dialogue are integral and essential for peace and social cohesion in our society, the Dialogue Society has been a medium, facilitating a platform to all from faith and non-faith backgrounds. The Dialogue Society thrives on being more inclusive to those who might be overlooked in society as a group. Although women seem to be in the core of society as an essential element, the women who contravene the monotype identity tend to remain in the shadows. The media is not just used to get information but also used as a way of having a sense of belonging by the audience. The media creates collective imaginary identities for public opinion. It gathers the audience under one consensus and creates an identity for the people who share this consensus. Hence, a form of media functions as a medium for identity creation and representation. Therefore, the production and reproduction of stereotypes and a monotype representation of women and women of faith in media content are the primary sources of the public's general attitudes towards women of faith. In the context of this report, the media limits not only women's gender but also their religious identity. The monotype identity of women opposes the plurality of the concept of women. Notably, media outlets are criticised for not recognising the differences in women's identities. Women of faith are susceptible to the lack of representation or misrepresentation and get stuck between the roles constructed for their gender and religion. Women who do not fit in these policies' stereotypes get misrepresented or disregarded by the media. Moreover, policymakers also limit their scope to a single monotype of women's identity when policies are made, creating a public consensus around women of faith. As both these mediums lack representation or have very symbolic and distorted representations of women of faith, we strive to provide a platform for all women from faith and non-faith backgrounds. The Dialogue Society has organised women-only community events for women of faith to have a bottom-up approach, including interfaith knitting, reading, and cooking clubs. Several women-only courses have informed women of the importance of interfaith dialogue, promoting current best practices, and identifying and promoting promising future possibilities. We have hosted panel discussions and held women-only interfaith circles where women from different faith backgrounds came together to discuss boundaries within religion and what they believed to transgress their boundaries. Consequently, we organised a panel series to focus on the roles of women of faith within different areas of society, aiming to highlight their unique individual and shared experiences and bring to light issues of inequality that impact women of faith. Although women of faith exist within all areas of society, we chose to explore women's experiences within three different settings to give a breadth of understanding about women of faith's interactions within society. Therefore, we held a panel series titled 'Women of Faith', including three panels, each focusing on a particular area: Women of Faith in Community, Women of Faith in Public Service, and Women of Faith in Media. In this report, following the content analysis method to systematically sort the information gathered by the panel series, we have written a series of recommendations to address these issues in media and policymaking. This paper has a section on specific policy recommendations for those in decision-making positions in the community, public service, and media, according to the content and findings gathered. This report aims to initiate and provide interactive and transferable advice and guidance to those in a position. The policy paper gives insight to social workers, teachers, council members, liaison officers, academics and relevant stakeholders, policymakers, and people who wish to understand more about empowering women of faith and hearing their experiences. It also aims to inspire ongoing efforts and further action to accelerate the achievement of complete freedom of faith, gender equality in promoting, recommending, and implementing direct top-level policies for faith and gender equality, and ensuring that existing policies are gender-sensitive and practices are safe from gender-based and faith-based discrimination for women of faith. Finally, this report is to engage and illustrate the importance of allyship, the outstanding achievement through dialogue based on real-life experience, and facilitate resilient relationships among people of different religious positions. We call upon every reader of this report to join the efforts of the Dialogue Society in promoting an equal society for women of faith.
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Book chapters on the topic "Fic Proteins"

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Jayasinghe, Chamila. "Shark Fin Cartilage: Uses, Extraction and Composition Analysis." In Marine Proteins and Peptides, 523–31. Chichester, UK: John Wiley & Sons, Ltd, 2013. http://dx.doi.org/10.1002/9781118375082.ch27.

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Rajpal, Arvind, Pavel Strop, Yik Andy Yeung, Javier Chaparro-Riggers, and Jaume Pons. "Introduction: Antibody Structure and Function." In Therapeutic Fc-Fusion Proteins, 1–44. Weinheim, Germany: Wiley-VCH Verlag GmbH & Co. KGaA, 2013. http://dx.doi.org/10.1002/9783527675272.ch01.

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Berry, Jody D., Catherine Yang, Janean Fisher, Ella Mendoza, Shanique Young, and Dwayne Stupack. "Fc-Fusion Protein Expression Technology." In Therapeutic Fc-Fusion Proteins, 45–66. Weinheim, Germany: Wiley-VCH Verlag GmbH & Co. KGaA, 2013. http://dx.doi.org/10.1002/9783527675272.ch02.

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Huang, Yao-Ming, Rashmi Kshirsagar, Barbara Woppmann, and Thomas Ryll. "Cell Culture-Based Production." In Therapeutic Fc-Fusion Proteins, 67–96. Weinheim, Germany: Wiley-VCH Verlag GmbH & Co. KGaA, 2013. http://dx.doi.org/10.1002/9783527675272.ch03.

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Shukla, Abhinav A., and Uwe Gottschalk. "Downstream Processing of Fc-Fusion Proteins." In Therapeutic Fc-Fusion Proteins, 97–114. Weinheim, Germany: Wiley-VCH Verlag GmbH & Co. KGaA, 2013. http://dx.doi.org/10.1002/9783527675272.ch04.

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Cao, Wenjin, Deirdre Murphy Piedmonte, Margaret Speed Ricci, and Ping Y. Yeh. "Formulation, Drug Product, and Delivery: Considerations for Fc-Fusion Proteins." In Therapeutic Fc-Fusion Proteins, 115–54. Weinheim, Germany: Wiley-VCH Verlag GmbH & Co. KGaA, 2013. http://dx.doi.org/10.1002/9783527675272.ch05.

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Eon-Duval, Alex, Ralf Gleixner, Pascal Valax, Miroslav Soos, Benjamin Neunstoecklin, Massimo Morbidelli, and Hervé Broly. "Quality by Design Applied to a Fc-Fusion Protein: A Case Study." In Therapeutic Fc-Fusion Proteins, 155–89. Weinheim, Germany: Wiley-VCH Verlag GmbH & Co. KGaA, 2013. http://dx.doi.org/10.1002/9783527675272.ch06.

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Idusogie, Esohe, and Michael Mulkerrin. "Analytical Methods Used to Characterize Fc-Fusion Proteins." In Therapeutic Fc-Fusion Proteins, 191–216. Weinheim, Germany: Wiley-VCH Verlag GmbH & Co. KGaA, 2013. http://dx.doi.org/10.1002/9783527675272.ch07.

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Berry, Jody D. "Introduction to Therapeutic Fc-Fusion Proteins." In Therapeutic Fc-Fusion Proteins, 217–32. Weinheim, Germany: Wiley-VCH Verlag GmbH & Co. KGaA, 2013. http://dx.doi.org/10.1002/9783527675272.ch08.

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Farson, Deborah A. "Alefacept." In Therapeutic Fc-Fusion Proteins, 233–54. Weinheim, Germany: Wiley-VCH Verlag GmbH & Co. KGaA, 2013. http://dx.doi.org/10.1002/9783527675272.ch09.

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Conference papers on the topic "Fic Proteins"

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Scherer, N. F., L. W. Ungar, D. C. Arnett, L. D. Book, H. Hu, and G. A. Voth. "Charge-Transfer Dynamics in Blue Copper Proteins: Experiment and Simulation." In International Conference on Ultrafast Phenomena. Washington, D.C.: Optica Publishing Group, 1996. http://dx.doi.org/10.1364/up.1996.fc.4.

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Blue copper proteins function as mobile electron carriers in biological systems by transfering electrons to and from their "type I" copper active sites liganded to the protein matrix.1 In reduced form, these active sites have a strong ligand-to-metal charge transfer transition between the copper atom and a cysteine sulfur ligand in the region of 595-630 nm, which gives the proteins their characterisitic blue color.2 This strong absorption makes blue copper proteins suitable for ultrafast spectroscopic studies of protein electron transfer. Elucidation of electronic and nuclear dynamics of these systems requires classical and quantum simulations in conjunction with experiment. The resultant spectral density describing the optically induced charge transfer process may be useful in understanding the long range electron transfer of physiological function.
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Freeman, L., V. Hornsey, D. S. Pepper, P. R. Foster, L. Winkelman, and J. Dawes. "PROTEIN AGGREGATES IN HEATED BLOOD PRODUCTS." In XIth International Congress on Thrombosis and Haemostasis. Schattauer GmbH, 1987. http://dx.doi.org/10.1055/s-0038-1644019.

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Heating of blood products to reduce viral infectivity is now a standard practice. Such treatment may also modify the constituent proteins, reducing their activity or altering their structure with potentially harmful consequences for the recipient. Partially denatured proteins frequently form aggregates, which are often immunogenic and could precipitate immune complex formation, allergic reactions and kidney damage. In addition they may contribute to the development of AIDS after HIV infection by inducing a persistent state of T-cell activation.Protein aggregate formation in factor VIII and factor IX (II + X) concentrates has been investigated by fast protein liquid chromatography (FPLC), which proved to be a rapid, convenient method for this purpose. Freeze-drying alone resulted in aggregate formation in intermediate purity FVIII concentrates, but not in FIX concentrates. However, aggregates were detected after heating the FIX concentrate at 80°C for 72h in the dry state. Dry heating of intermediate purity FVIII concentrates to 68°C for 24h also increased the content of protein aggregates, which contained fibrinogen and fibronectin but little IgG. In this product, the aggregate content after heating correlated with total protein concentration. A higher purity FVIII concentrate selectively depleted in fibrinogen and fibronectin also contained protein aggregates after freeze-drying, but heating this product at 80°C for 72h resulted in a relatively small increase in aggregate content. Haemophiliacs receiving regular injections of heated concentrates are constantly exposed to protein aggregates. They should be monitored for any harmful effects, and manufacturers should aim to reduce the aggregate content of their products.
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Jorgensen, M. J., MJ Rabiet, A. B. Cantor, B. Furie, C. L. Brown, C. B. Shoemaker, and B. C. Furie. "VITAMIN K-DEPENDENT γ-CARBOXYLATION OF FACTOR IX REQUIRES A RECOGNITION SITE CONTAINED WITHIN THE PROPEPTIDE." In XIth International Congress on Thrombosis and Haemostasis. Schattauer GmbH, 1987. http://dx.doi.org/10.1055/s-0038-1643564.

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The vitamin K-dependent proteins, including Factor IX (FIX), are calcium-binding proteins that undergo vitamin K-dependent post-translational modification to convert amino terminal glutamic aoid residues to Gla residues. Sequence homology among the propeptides of these proteins suggests a role for this region in designating the adjacent glutamic acid-rich domain for γ-carboxylation during intraoellular processing. Mutations vere made in the propeptide (residues -1 to -18) of FIX, and the effects on γ-carboxylation were assessed. The human FIX cDNA coding sequenoe was modified using oligonucleotide-directed site-specific mutagenesis and was expressed in Chinese hamster ovary cells. The extent of γ-carboxylation of secreted FIX was determined by (1) ability to interact with conformation-specific antibodies directed against the Gla-dependent, metal-stabilized, native structure of FIX, and (2) direct Gla analysis of the alkaline hydrolysate. Using the unmodified coding sequence, 64 ± 17 % of recombinant Factor IX bound to the conformation-specific antibodies, and 9.4 ± 0.7 Gla residues were found (compared with 12 Gla in plasma FIX). When the 18-residue propeptide was deleted, secreted FIX contained no detectable native FIX antigen and no detectable Gla. Similarly, point mutations leading to substitution of Ala for Phe at residue -16 or Glu for Ala at residue -10 led to secretion of FIX containing 2% and 6% native antigen, respectively, and approximately 1-2 Gla residues. The molecular weight of each of the reoombinant FIX species, as estimated by SDS-PAGE, was identical to that of plasma FIX. NH2-terminal sequence analysis of the mutant FIX speoies yielded the NH2-terminal sequence of plasma FIX. These data indicate that the mutations made in the propeptide did not interfere with intracellular proteolytic prooessing of FIX. We conolude that the FIX propeptide participates in defining a recognition site that designates an adjacent glutamic acid-rich domain for γ-carboxylation. The association of the propeptide with the γ-carboxylation recognition site provides the first demonstration of a specific function served by a propeptide in post-translational protein processing.
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Corredig, Milena. "Processing plant proteins colloidal structures." In 2022 AOCS Annual Meeting & Expo. American Oil Chemists' Society (AOCS), 2022. http://dx.doi.org/10.21748/cyqr3105.

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Food systems need to be designed to better fit within planetary boundaries. It is not only important to find more sustainable protein sources, but also to create fully circular, robust supply chains. But this is only the beginning: new formulations will need to fit common dietary expectations. The utilization of plant-based protein ingredients present significant challenges in relation to their nutritional and technological functionalities. Today these proteins do not measure up when used as ingredients in conventional processes. Plant protein streams contain polydisperse colloids, and detailed studies of their behaviour during processing is only at their infancy. To predict their structure-function, their physical and chemical changes need to be followed at various length scales. Furthermore, for each food matrix, depending on the final product needs, it will be required to find the appropriate level of refinement and processing history, to reach the right balance between sustainability and processing/nutritional functionality. This is currently a significant knowledge gap. This talk will outline how processing dynamics at the molecular and supramolecular level, affect the interactions occurring with the various components in mixed matrices, and will aim to inspire researchers to find new processing and formulation approaches that will better fit plant-based ingredients utilization, and with this accelerate progress towards a shift to more sustainable diets.
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Reisner, H. M., M. de Serres, S.-W. Lin, and D. W. Stafford. "PROPERTIES OF MONOCLONAL ANTIBODIES TO HUMAN FACTOR IX-PHAGE CAP-SID FUSION PROTEIN." In XIth International Congress on Thrombosis and Haemostasis. Schattauer GmbH, 1987. http://dx.doi.org/10.1055/s-0038-1644080.

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Functional domains of the human factor IX (FIX) molecule may be expressed in E. coli as fusion proteins (FPs) with phage T7 capsid protein 10 (CP 10). Such proteins are synthesized in large amounts and, because of their insolubility can be easily purified Polyclonal antibodies raised to FIX FPs cross react with the native molecule, but the utility of FPs in the production of monoclonal probes of native FIX is unclear. Hence, we have characterized the specificity of murine hybridomas resulting from the immunization with a FP containing amino acids -3 to 49 of human FIX (FP4D) . FP4D proved to be a potent immunogen in mice. Using solid phase ELISA assays, 46% of 2,200 cultures screened reacted with the immunizing antigen. Most of the positive cultures reacted only with FP4D and/or CP 10 and were discarded. Fifty cultures reacted with native FIX and were further studied. None of the FIX reactive cultures inhibited FIX:C activity in clotting assays. Binding of more than half of the cultures to FIX was inhibited by the presence of 5mM Ca++ suggesting a similarity between FP4D and the non Ca++ bound steric state of FIX. Four cultures were subcloned 2X to insure monoclonality. These antibodies were further evaluated for binding to FIX, FP4D, and CP 10 in the presence or absence of Ca++. Three of the four Mabs reacted with FP4D and FIX and showed varying degrees of inhibition by Ca++ only with FIX. One antibody reacted equally with all three proteins in the presence or absence of Ca++. Two of the Mabs were detectable in a solid phase RIA and showed increased radioligand binding in the absence of Ca++. Most Mabs against FP4D appear to detect epitopes which are influenced by the presence of Ca++. Since the FIX amino acid sequence contained in FP4D is gammacarboxylated and capable of binding Ca++ in the native molecule, the epitopes detected by these Mabs may be masked or altered by Ca++ binding. These Mabs may prove to be useful probes in the study of Ca++ binding in the native FIX molecule.
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Kim, Sungwon S., Tom T. Huang, Timothy S. Fisher, and Michael R. Ladisch. "Effects of Carbon Nanotube Structure on Protein Adsorption." In ASME 2005 International Mechanical Engineering Congress and Exposition. ASMEDC, 2005. http://dx.doi.org/10.1115/imece2005-81395.

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Outstanding transport characteristics and high surface-to-volume ratios are several advantages that carbon nanotubes possess that make them attractive candidates for protein immobilization matrices in biosensor applications. A further advantage of using carbon nanotubes is that their structure (e.g., diameter, length, density) can potentially be controlled during synthesis. In the present study, the effects of carbon nanotube structure on enzyme immobilization onto carbon nanotube arrays are investigated. Bovine serum albumin (BSA) serves as both a blocking agent for prevention of nonspecific adsorption and as a support for anchoring bioreceptors. BSA, a globular protein having a 4 to 6 nm characteristic dimension, is stably adsorbed through mechanisms that involve hydrophobic interactions between surfaces presented by the carbon nanotubes and the spacing between the nanotubes with the protein. Protein adsorption is confirmed by fluorescence microscopy of surfaces that have been exposed to fluourescein isothiocyanate (FITC) labeled BSA. The adsorption of biotinylated BSA can be used, through a sandwich immobilization scheme, to provide an anchor for streptavidin, which in turn has at least one other adsorption site that is specific for other biotinylated proteins such as glucose oxidase that would form a biorecognition or catalytic element in a functional biosensor. Correlation between carbon nanotube structure and protein adsorption at the nano-bio interface could eventually lead to growth conditions that yield carbon nanotubes for biosensor applications with optimal protein adsorption characteristics.
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7

Delani, F., M. Tagliaferri, D. Macconi, C. Lupini, N. Perico, and G. Rumuzzi. "PLATELET ACTIVATING FACTOR (PAF) AS A MEDIATOR OF PROTEINURIA IN ISOLATED PERFUSED KIDNEY (IPK)." In XIth International Congress on Thrombosis and Haemostasis. Schattauer GmbH, 1987. http://dx.doi.org/10.1055/s-0038-1643485.

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PAF amplifies tissue damage in glomerulonephritis and can promote proteinuria stimulating platelet and neutrophil cationic protein release. We used IPK to establish whether PAF directly causes proteinuria. Kidneys were isolated from male Sprague-Dawley rats and perfused at constant pressure (100 mmHg) in a closed circuit with a Krebs-Henseleit buffer containing glucose urea creatinine, BSA (1%), Ficoll 70 (3.5%) and amino acids. After 25 min stabilization period, a basal 10 min clearance period was followed by PAF (1.8 nM f.c. n = 6) or vehicle (n = 5) injection into the renal artery. As seen in the figure PAF but not vehicle significantly (p<0.01) increased urine protein excretion. No significant changes in GFR (as creatinine clearance) were observed after PAF or vehicle injection (Basal: 0.786 ± 0.075 PAF: 0.658 ± 0.070. Basal 0.653 ± 0.081, vehicle 0.639 ± 0.074 ml/min/g kidney). The data indicate that PAF may directly increase glomerular permeability to proteins.
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8

Li, He, and George Lykotrafitis. "Modeling Diffusion and Vesiculation in Defective Human Erythrocyte Membrane." In ASME 2013 Summer Bioengineering Conference. American Society of Mechanical Engineers, 2013. http://dx.doi.org/10.1115/sbc2013-14203.

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The hemolytic disorders of hereditary spherocytosis (HS) and hereditary elliptocytosis (HE) affect the lives of millions of individuals worldwide. In HS and HE, connections in the vertical and horizontal directions between components of the RBC membrane (see Fig. 1(a)), are disrupted due to defective proteins, leading to loss of the structural and functional integrity of the membrane (1–2). Moreover, disruptions of either the vertical interactions or horizontal interactions affect the lateral diffusivity of the mobile band 3 proteins, as the motion of band 3 in the RBC membrane is confined by the cytoskeleton (3). Although a number of coarse-grained molecular dynamics (CGMD) RBC membrane models have been developed in the past two decades, very few RBC membrane models have been used to study the disordered band 3 diffusion and membrane vesiculation in HS and HE. The implicit representations of either the lipid bilayer or the cytoskeleton in these membrane models limit their applications in the membrane instability problems in HS and HE. In this extended abstract, we develop a two-component CGMD human RBC membrane model that explicitly comprises both the lipid bilayer and the cytoskeleton. In this way, the interactions between the cytoskeleton and the proteins embedded in the lipid bilayer can be simulated. The proposed model allows us to measure the band 3 lateral mobility and simulate the process of membrane vesiculation in the membrane with protein defects.
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9

de Serres, M., H. M. Reisner, D. Monroe, and H. Roberts. "A MONOCLONAL ANTIBODY WHOSE BINDING IS INHIBITED BY DIVALENT CATIONS." In XIth International Congress on Thrombosis and Haemostasis. Schattauer GmbH, 1987. http://dx.doi.org/10.1055/s-0038-1644075.

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Factor IX (FIX), a vitamin K dependent coagulation protein, is functionally deficient or absent in patients with hemophilia B. Binding of Ca++ by the gammacarboxyglutamic acid residues (Gla) of FIX is necessary for coagulant activity. Antibodies havebeendes-cribed which selectively bind to FIX in the presence of Ca++ and appear to interact with Ca-H- stabilized epitopes of FIX. One IgM, Kappa murine monoclonal antibody (Mab), 129-1, has been found to react preferentially with FIX in the absence of Ca-H- or with FIX having a reduction in gammacarboxylation. 129-1 was characterized by direct binding ELISA assays, the standard assay buffer (.02M Tris - .15M NaCL pH 7.5) was supplemented with Ca-H- or ED TA to final concentrations to 5mM and lOmM respectively. In the presence of Ca-H-, titers ranged from 10 to 100 as compared to 100 K to 500 K in the presence of EDTA. Control Mab's, FIX-30 and 2D521 showed no such effect. Maximum inhibition occurred ≥2.5 mM Ca-H- concentration. Mg++, Sr-H- and Mn-H- were tested with similar results. Chemically degammacarboxylated FIXa was compared to FIX and FIXa controls in the presence of Ca-H- or EDTA, to determine the importance of Gla residues. In the presence of EDTA, Mab 129-1 had essentially equal reactivity with all these proteins (titers 100 K). In the presence of Ca-H-, binding to FIX and FIXa was inhibited (500 and 1 K respectively). However, the binding to Gla modified FIXa in the presence of Ca-H- was only slightly reduced (10 K), suggesting the importance of Gla residues in the Ca-H- mediated inhibition. FIX was purified from concentrate, coumadinized plasma and culture supernatant (produced in the absence of vitamin K) from the cell line PMN45 using HPLC affinity chromatography with Mab 2D521. Mab 129-1 binding to FIX immunopurified from concentrate and a control biochemically purified FIX protein preparation was significantly higher in the presence of EDTA (titers 500 and 5 K) than in Ca-H- (titers 10 and 10). FIX purified from coumadinized plasma or PMN45 cells showed equal low reactivity with 129-1 in the presence or absence of Ca-H- (titer 10 in all cases). FIX-30 and 2D521 controls showed no such reduction in binding. Therefore, Gla residues may play a role in the binding of 129-1 to FIX.
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Chiu, Hui-Ling, John Deak, and R. J. Dwayne Miller. "The Primary Processes in Heme Protein Relaxation: The Coupled Reaction Coordinate Problem in Molecular Cooperativity." In International Conference on Ultrafast Phenomena. Washington, D.C.: Optica Publishing Group, 1996. http://dx.doi.org/10.1364/up.1996.fc.3.

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The phenomena of molecular cooperativity involves an interaction between two or more different protein moieties in which the protein's function is controlled synergistically by its neighbor. Changes in state of the adjacent protein, such as changes in ligation of a receptor molecule, affect the reaction rate of its neighbor, often several nanometers away. The reaction rate can be controlled by either changes in the reaction free energy or activation barriers. Our current understanding of this process is based on structural changes at one site affecting the adjacent activation barrier. In order to affect a reaction coordinate at a distance, these structural changes must involve highly correlated atomic displacements coupling thousands of degrees of freedom. The key question then is what is the mechanism by which the reaction forces at one site propagate to adjacent sites, i.e., what is the communication pathway? How do the reaction forces which develop on an atomic length scale couple to mesoscopic dimensions of motion?
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Reports on the topic "Fic Proteins"

1

Ohad, Nir, and Robert Fischer. Regulation of Fertilization-Independent Endosperm Development by Polycomb Proteins. United States Department of Agriculture, January 2004. http://dx.doi.org/10.32747/2004.7695869.bard.

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Arabidopsis mutants that we have isolated, encode for fertilization-independent endosperm (fie), fertilization-independent seed2 (fis2) and medea (mea) genes, act in the female gametophyte and allow endosperm to develop without fertilization when mutated. We cloned the FIE and MEA genes and showed that they encode WD and SET domain polycomb (Pc G) proteins, respectively. Homologous proteins of FIE and MEA in other organisms are known to regulate gene transcription by modulating chromatin structure. Based on our results, we proposed a model whereby both FIE and MEA interact to suppress transcription of regulatory genes. These genes are transcribed only at proper developmental stages, as in the central cell of the female gametophyte after fertilization, thus activating endosperm development. To test our model, the following questions were addressed: What is the Composition and Function of the Polycomb Complex? Molecular, biochemical, genetic and genomic approaches were offered to identify members of the complex, analyze their interactions, and understand their function. What is the Temporal and Spatial Pattern of Polycomb Proteins Accumulation? The use of transgenic plants expressing tagged FIE and MEA polypeptides as well as specific antibodies were proposed to localize the endogenous polycomb complex. How is Polycomb Protein Activity Controlled? To understand the molecular mechanism controlling the accumulation of FIE protein, transgenic plants as well as molecular approaches were proposed to determine whether FIE is regulated at the translational or posttranslational levels. The objectives of our research program have been accomplished and the results obtained exceeded our expectation. Our results reveal that fie and mea mutations cause parent-of-origin effects on seed development by distinct mechanisms (Publication 1). Moreover our data show that FIE has additional functions besides controlling the development of the female gametophyte. Using transgenic lines in which FIE was not expressed or the protein level was reduced during different developmental stages enabled us for the first time to explore FIE function during sporophyte development (Publication 2 and 3). Our results are consistent with the hypothesis that FIE, a single copy gene in the Arabidopsis genome, represses multiple developmental pathways (i.e., endosperm, embryogenesis, shot formation and flowering). Furthermore, we identified FIE target genes, including key transcription factors known to promote flowering (AG and LFY) as well as shoot and leaf formation (KNAT1) (Publication 2 and 3), thus demonstrating that in plants, as in mammals and insects, PcG proteins control expression of homeobox genes. Using the Yeast two hybrid system and pull-down assays we demonstrated that FIE protein interact with MEA via the N-terminal region (Publication 1). Moreover, CURLY LEAF protein, an additional member of the SET domain family interacts with FIE as well. The overlapping expression patterns of FIE, with ether MEA or CLF and their common mutant phenotypes, demonstrate the versatility of FIE function. FIE association with different SET domain polycomb proteins, results in differential regulation of gene expression throughout the plant life cycle (Publication 3). In vitro interaction assays we have recently performed demonstrated that FIE interacts with the cell cycle regulatory component Retinobalsoma protein (pRb) (Publication 4). These results illuminate the potential mechanism by which FIE may restrain embryo sac central cell division, at least partly, through interaction with, and suppression of pRb-regulated genes. The results of this program generated new information about the initiation of reproductive development and expanded our understanding of how PcG proteins regulate developmental programs along the plant life cycle. The tools and information obtained in this program will lead to novel strategies which will allow to mange crop plants and to increase crop production.
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2

Ohad, Nir, and Robert Fischer. Control of Fertilization-Independent Development by the FIE1 Gene. United States Department of Agriculture, August 2000. http://dx.doi.org/10.32747/2000.7575290.bard.

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A fundamental problem in biology is to understand how fertilization initiates reproductive development. During plant reproduction, one sperm cell fuses with the egg to form an embryo, whereas a second sperm cell fuses with the adjacent central cell nucleus to form the endosperm tissue that supports embryo and/or seedling development. To understand the mechanisms that initiate reproduction, we have isolated mutants of Arabidopsis that allow for replication of the central cell and subsequent endosperm development without fertilization. In this project we have cloned the MEA gene and showed that it encode a SET- domain polycomb protein. Such proteins are known to form chromatin-protein complexes that repress homeotic gene transcription and influence cell proliferation from Drosophylla to mammals. We propose a model whereby MEA and an additional polycomb protein we have cloned, FIE , function to suppress a critical aspect of early plant reproduction and endosperm development, until fertilization occurs. Using a molecular approach we were able to determine that FIE and MEA interact physically, suggesting that these proteins have been conserved also during the evolution of flowering plants. The analysis of MEA expression pattern revealed that it is an imprinted gene that displays parent-of- origin-dependent monoallelic expression specifically in the endosperm tissue. Silencing of the paternal MEA allele in the endosperm and the phenotype of mutant mea seeds support the parental conflict theory for the evolution of imprinting in plants and mammals. These results contribute new information on the initiation of endosperm development and provide a unique entry point to study asexual reproduction and apomixis which is expected to improve crop production.
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3

Ohad, Nir, and Robert Fischer. Regulation of plant development by polycomb group proteins. United States Department of Agriculture, January 2008. http://dx.doi.org/10.32747/2008.7695858.bard.

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Our genetic and molecular studies have indicated that FIE a WD-repeat Polycomb group (PcG) protein takes part in multi-component protein complexes. We have shown that FIE PcG protein represses inappropriate programs of development during the reproductive and vegetative phases of the Arabidopsis life cycle. Moreover, we have shown that FIE represses the expression of key regulatory genes that promote flowering (AG and LFY), embryogenesis (LEC1), and shoot formation (KNAT1). These results suggest that the FIE PcG protein participates in the formation of distinct PcG complexes that repress inappropriate gene expression at different stages of plant development. PcG complexes modulate chromatin compactness by modifying histones and thereby regulate gene expression and imprinting. The main goals of our original project were to elucidate the biological functions of PcG proteins, and to understand the molecular mechanisms used by FIE PcG complexes to repress the expression of its gene targets. Our results show that the PcG complex acts within the central cell of the female gametophyte to maintain silencing of MEA paternal allele. Further more we uncovered a novel example of self-imprinting mechanism by the PgG complex. Based on results obtained in the cures of our research program we extended our proposed goals and elucidated the role of DME in regulating plant gene imprinting. We discovered that in addition to MEA,DME also imprints two other genes, FWA and FIS2. Activation of FWA and FIS2 coincides with a reduction in 5-methylcytosine in their respective promoters. Since endosperm is a terminally differentiated tissue, the methylation status in the FWA and FIS2 promoters does not need to be reestablished in the following generation. We proposed a “One-Way Control” model to highlight differences between plant and animal genomic imprinting. Thus we conclude that DEMETER is a master regulator of plant gene imprinting. Future studies of DME function will elucidate its role in processes and disease where DNA methylation has a key regulatory role both in plants and animals. Such information will provide valuable insight into developing novel strategies to control and improve agricultural traits and overcome particular human diseases.
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4

Kirchhoff, Helmut, and Ziv Reich. Protection of the photosynthetic apparatus during desiccation in resurrection plants. United States Department of Agriculture, February 2014. http://dx.doi.org/10.32747/2014.7699861.bard.

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In this project, we studied the photosynthetic apparatus during dehydration and rehydration of the homoiochlorophyllous resurrection plant Craterostigmapumilum (retains most of the photosynthetic components during desiccation). Resurrection plants have the remarkable capability to withstand desiccation, being able to revive after prolonged severe water deficit in a few days upon rehydration. Homoiochlorophyllous resurrection plants are very efficient in protecting the photosynthetic machinery against damage by reactive oxygen production under drought. The main purpose of this BARD project was to unravel these largely unknown protection strategies for C. pumilum. In detail, the specific objectives were: (1) To determine the distribution and local organization of photosynthetic protein complexes and formation of inverted hexagonal phases within the thylakoid membranes at different dehydration/rehydration states. (2) To determine the 3D structure and characterize the geometry, topology, and mechanics of the thylakoid network at the different states. (3) Generation of molecular models for thylakoids at the different states and study the implications for diffusion within the thylakoid lumen. (4) Characterization of inter-system electron transport, quantum efficiencies, photosystem antenna sizes and distribution, NPQ, and photoinhibition at different hydration states. (5) Measuring the partition of photosynthetic reducing equivalents between the Calvin cycle, photorespiration, and the water-water cycle. At the beginning of the project, we decided to use C. pumilum instead of C. wilmsii because the former species was available from our collaborator Dr. Farrant. In addition to the original two dehydration states (40 relative water content=RWC and 5% RWC), we characterized a third state (15-20%) because some interesting changes occurs at this RWC. Furthermore, it was not possible to detect D1 protein levels by Western blot analysis because antibodies against other higher plants failed to detect D1 in C. pumilum. We developed growth conditions that allow reproducible generation of different dehydration and rehydration states for C. pumilum. Furthermore, advanced spectroscopy and microscopy for C. pumilum were established to obtain a detailed picture of structural and functional changes of the photosynthetic apparatus in different hydrated states. Main findings of our study are: 1. Anthocyan accumulation during desiccation alleviates the light pressure within the leaves (Fig. 1). 2. During desiccation, stomatal closure leads to drastic reductions in CO2 fixation and photorespiration. We could not identify alternative electron sinks as a solution to reduce ROS production. 3. On the supramolecular level, semicrystalline protein arrays were identified in thylakoid membranes in the desiccated state (see Fig. 3). On the electron transport level, a specific series of shut downs occur (summarized in Fig. 2). The main events include: Early shutdown of the ATPase activity, cessation of electron transport between cyt. bf complex and PSI (can reduce ROS formation at PSI); at higher dehydration levels uncoupling of LHCII from PSII and cessation of electron flow from PSII accompanied by crystal formation. The later could severe as a swift PSII reservoir during rehydration. The specific order of events in the course of dehydration and rehydration discovered in this project is indicative for regulated structural transitions specifically realized in resurrection plants. This detailed knowledge can serve as an interesting starting point for rationale genetic engineering of drought-tolerant crops.
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5

Walsh, Alex. The Contentious Politics of Tunisia’s Natural Resource Management and the Prospects of the Renewable Energy Transition. Institute of Development Studies (IDS), February 2021. http://dx.doi.org/10.19088/k4d.2021.048.

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For many decades in Tunisia, there has been a robust link between natural resource management and contentious national and local politics. These disputes manifest in the form of protests, sit-ins, the disruption of production and distribution and legal suits on the one hand, and corporate and government response using coercive and concessionary measures on the other. Residents of resource-rich areas and their allies protest the inequitable distribution of their local natural wealth and the degradation of their health, land, water, soil and air. They contest a dynamic that tends to bring greater benefit to Tunisia’s coastal metropolitan areas. Natural resource exploitation is also a source of livelihoods and the contentious politics around them have, at times, led to somewhat more equitable relationships. The most important actors in these contentious politics include citizens, activists, local NGOs, local and national government, international commercial interests, international NGOs and multilateral organisations. These politics fit into wider and very longstanding patterns of wealth distribution in Tunisia and were part of the popular alienation that drove the uprising of 2011. In many ways, the dynamic of the contentious politics is fundamentally unchanged since prior to the uprising and protests have taken place within the same month of writing of this paper. Looking onto this scene, commentators use the frame of margins versus centre (‘marginalization’), and also apply the lens of labour versus capital. If this latter lens is applied, not only is there continuity from prior to 2011, there is continuity with the colonial era when natural resource extraction was first industrialised and internationalised. In these ways, the management of Tunisia’s natural wealth is a significant part of the country’s serious political and economic challenges, making it a major factor in the street politics unfolding at the time of writing.
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