Thèses sur le sujet « Conserved region »
Pour voir les autres types de publications sur ce sujet consultez le lien suivant : Conserved region.
Créez une référence correcte selon les styles APA, MLA, Chicago, Harvard et plusieurs autres
Consultez les 50 meilleures thèses pour votre recherche sur le sujet « Conserved region ».
À côté de chaque source dans la liste de références il y a un bouton « Ajouter à la bibliographie ». Cliquez sur ce bouton, et nous générerons automatiquement la référence bibliographique pour la source choisie selon votre style de citation préféré : APA, MLA, Harvard, Vancouver, Chicago, etc.
Vous pouvez aussi télécharger le texte intégral de la publication scolaire au format pdf et consulter son résumé en ligne lorsque ces informations sont inclues dans les métadonnées.
Parcourez les thèses sur diverses disciplines et organisez correctement votre bibliographie.
1
Severi, Emmanuele. « The role of the conserved carboxy-terminal region of the Escherichia coli ammonium channel AmtB ». Thesis, University of East Anglia, 2005. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.426575.
Texte intégral
2
Zhang, Xiaoyan. « Phosphorothioate hammerhead ribozymes targeting a conserved sequence in V3 loop region inhibit HIV-1 infection ». Kyoto University, 1999. http://hdl.handle.net/2433/181687.
Texte intégral
3
Eno-Ibanga, Cheryl K. « The analysis of a conserved RNA structure in the 3D polymerase encoding region of human parechovirus 1 ». Thesis, University of Essex, 2016. http://repository.essex.ac.uk/19097/.
Texte intégralRésumé :
Picornaviruses are important causes of human illness and it is necessary to understand more about how these viruses function. Human parechoviruses (HPeV) are common pathogens and studies have shown that 95% of people become infected with HPeV at a very early age, usually with symptoms such as mild diarrhoea and fever. However, one virus type HPeV3, is implicated in much more serious cases of neonatal disease and so it is important to understand HPeVs to increase the opportunity to develop drugs or vaccines against the infection. The HPeV1 genome encodes a single polyprotein that is cleaved into structural and non-structural proteins. Analysis of one region of the genome (encoding the polymerase, 3Dpol) shows that some codons are perfectly conserved, suggesting functions in addition to protein coding. This region seems to fold into an RNA secondary structure made up of three stem-loops and a tertiary structure “kissing” interaction. The structure was validated by comparing all the available HPeV sequences and found to be highly conserved. To investigate if the structure has a role in RNA stability, an EGFP fluorescent assay was used. Sequences containing the structure was added to the 3’ UTR of the EGFP gene. A mutant with 21 mutations which completely destroys the RNA structure was also used. A FACS-based method was used to measure expression levels of EGFP. The results showed that there was a significant reduction in fluorescence from the mutant construct. The effect of the structure was also investigated in infected cells and in cells exposed to different stresses which could mimic virus infection. The results suggest that the structure can positively affect RNA stability/translation. Further investigation on other possible roles such as RNA replication and translation should be performed to improve the understanding of the biology of the structure in HPeVs and a Renilla Luciferase reporter gene system was assembled to facilitate the studies in the future.
4
Ahmed, Tina May. « Characterisation of T cells induced by candidate conserved region HIV-1 vaccines in healthy HIV-1/2 negative volunteers ». Thesis, University of Oxford, 2014. http://ora.ox.ac.uk/objects/uuid:8d06f1f6-dd2a-4be1-b66c-936c5d006f38.
Texte intégralRésumé :
HIV-1 has claimed the lives of millions of people globally and continues to spread despite development of highly active antiretroviral therapy. In 2013, 2.1 million new infections occurred and over 35 million people were living with HIV-1 infection. A prophylactic HIV-1 vaccine that can prevent infection or reduce viremia and subsequent transmission will always be an important part of the solution to bring this epidemic under control. In this thesis, the first HIV-1 vaccine candidate to focus on conserved regions of the virus (HIVconsv) was assessed in a phase I clinical trial conducted in healthy HIV-1/2 negative volunteers in Oxford. The HIVconsv T-cell immunogen was delivered using three leading vaccine modalities (DNA (D), modified vaccinia virus Ankara (M) and chimpanzee adenovirus serotype 63 (C)), in several novel heterologous prime-boost regimens. The frequency of T cells elicited through HIVconsv vaccination in the CM and DDDCM regimens surpassed that of previous HIV-1 cell-mediated vaccines. A large proportion of these T cells produced multiple cytokines and proliferated in response to recall peptides. The breadth of T-cell responses were also greater than the non-efficacious STEP study vaccine, with an average of 10 T-cell epitopes per vaccine recipient recognised across CM and DDDCM regimens. In vitro HIV-1 control mediated by CD8⁺ T cells was demonstrated for all vaccinees receiving the CM regimen, mainly against clade A (U455) and clade B (IIIB) isolates. Two vaccinees, demonstrated superior control of 6/8 and 7/8 viruses from the panel. The CM regimen induced significantly higher magnitudes of viral inhibition compared to the DDDCM or DDDMC regimens, with this regimen showing potential to overcome the disadvantage for subjects of carrying non-protective HLA alleles. Investigation of T-cell specificities revealed that the frequencies of T cells specific for conserved Gag but more so Pol regions significantly correlated with in vitro virus control. Direct examination of peptide expanded T-cell lines showed that all Pol pool- and limited Gag pool-specific cell lines reduced HIV-1 replication in vitro. In most individuals, targeting multiple HIV-1 epitopes concomitantly resulted in higher levels of virus inhibition than targeting a single viral epitope and two T-cell specificities showed enhanced control of HIV-1; the first within Pol (TAFTIPSI) and second from Gag (TERQANFL). These data support further development of the conserved region strategy for T-cell vaccines against HIV-1.
5
Wang, Yibing. « Study of cysteines in the stalk region of CD3 proteins : evolutionarily conserved residues critical for T cell development and function / ». Connect to full text via ProQuest. Limited to UCD Anschutz Medical Campus, 2008.
Trouver le texte intégralRésumé :
Thesis (Ph.D. in Immunology) -- University of Colorado Denver, 2008.Typescript. Includes bibliographical references (leaves 138-153). Free to UCD Anschutz Medical Campus. Online version available via ProQuest Digital Dissertations;
6
Van, Vleet Eric. « From Passive to Active Community Conservation : A Study of Forest Governance in a Region of the Sierra Norte of Oaxaca, Mexico ». FIU Digital Commons, 2013. http://digitalcommons.fiu.edu/etd/823.
Texte intégralRésumé :
This thesis investigates how seven communities in a subregion of the Sierra Norte of Oaxaca are conserving high forest cover in the absence of national protected areas. To conduct this study I relied on archival research and the review of community documents, focus group interviews and land use transects to explore historical and current land use. I found that communities have conserved 88.34% of the subregion as forest cover, or 58,596 hectares out of a total territory of 66,264 hectares. Analysis suggests that the communities have undergone a historical transition from more passive conservation to more active, conscious conservation particularly in the last decade. This thesis further contends that communities deserve additional financial compensation for this active conservation of globally important forests for biodiversity conservation and that exercises in systematic conservation planning ignore the reality that existing biodiversity conservation in the subregion is associated with community ownership.
7
Olinski, Robert Piotr. « Evolutionary Analysis of the Insulin-Relaxin Gene Family from the Perspective of Gene and Genome Duplication Events ». Doctoral thesis, Uppsala : Acta Universitatis Upsaliensis : Univ.-bibl. [distributör], 2007. http://urn.kb.se/resolve?urn=urn:nbn:se:uu:diva-7892.
Texte intégral
8
Xu, Lin. « HIV-1 mucosal immunity : from infection to prevention : HIV-1 envelope gp41 conserved region P1 modulates the mucosal innate immune response and acts as a potential mucosal adjuvant The HIV-1 viral synapse signals human foreskin keratinocytes to secrete thymic stromal lymphopoietin facilitating HIV-1 foreskin entry By shaping the antigen binding site in IgA, the CH1α domain is crucial for HIV-1 protection in highly exposed sero-negative individuals The antigen HIV-1 envelope gp41 conserved region P1 can act as mucosal adjuvant by modulating the innate immune response ». Thesis, Sorbonne Paris Cité, 2018. http://www.theses.fr/2018USPCB071.
Texte intégralRésumé :
La vaccination muqueuse, notamment celle administrée par voie nasale, est considérée comme la méthode optimale permettant de protéger les sites muqueux de l'infection par des pathogènes. Cependant, le manque d'adjuvants muqueux spécifiques ainsi qu'une prise en compte insuffisante du système immun nasal limite le développement des vaccins muqueux. P1, un domaine conservé de gp41, la glycoprotéine d'enveloppe du VIH-1, a été récemment utilisé par le laboratoire d'acceuil pour développer un vaccin prophylactique muqueux après immunisation combinée par voie nasale et intra-musculaire. Ce vaccin s'est montré efficace lors études pré-cliniques et clinique de Phase I chez l'Homme, grâce à sa capacité d'induire des IgA muqueux contre P1 bloquant la pénétration muqueuse du VIH-1 par transcytose et de stimuler la production d'IgG spécifiques de gp41 induisant la lyse des cellules infectées par le VIH-1 par cytotoxicité cellulaire médiée par anticorps (ADCC). Dans le travail présenté ici, nous avons caractérisé les mécanismes immuns induits par ce vaccin basé sur P1 au niveau de la muqueuse nasale humaine. Tout d'abord, nous avons démontré que P1 initie une réponse immune en induisant la sécrétion de la cytokine TH2, la Thymic Stromal LymphoPoietin (TSLP), par les cellules épithéliales nasales. TSLP est connyu pour ses propriétés d'adjuvant muqueux puissant et son récepteur, le TSLP-R, joue un rôle déterminant dans la réponse muqueuse à IgA. Nous avons montré que P1 induit l'expression de TSLP via l'interaction de P1 avec le galactosyl céramide, un récepteur du VIH-1 permettant l'entrée muqueuse du virus. De plus, nous avons identifié la voie de signalisation Calcineurin/NFATet le microRNA- comme partenaire décisifs dans la régulation de la production de TSLP induite par P1. Dans un second temps, nous avons montré que le peptide P1 module la réponse innée en activant les cellules dendritiques (DCs). Cette stimulation par P1 induit l'augmentation de l'expression des molécules de co-stimulation par les DCs. La sécrétion de l'IL-6 et de l'IL-10 par les DCs est aussi augmentée par P1 alors que celle de l'interféron gamma, IFN-', est réduite, démontrant ainsi que les DCs activée par P1 se polarisent en une phénotype facilitant une réponse Th2 et IgA. De plus, l'IL-8 et les chimiokines CCL20 et CCL22 sont secrétées indiquant que les DCs ont acquis la capacité de recruter des cellules immunes dans la muqueuse pour initier une réponse muqueuse adaptative. La métalloprotéinase MMP-9 permettant la dégradation de la matrice extracellulaire et facilitant la migration des cellules hors de la muqueuse, est aussi produite. Une boucle positive autocrine de TSLP est observée, puisque P1 induit la sécrétion par les DCs de TSLP en conséquence l'augmentation de l'expression du TSLP-R par les DCs induite par P1. Finalement, P1 active la prolifération des lymphocytes TCD4+ médiée par les DCs. En conclusion, nous avons démontré que P1 est un peptide multifonctionnel avec un grand potentiel dans le développement de vaccin, non seulement comme antigène vaccinal candidat mais aussi comme potentiel adjuvant qui pourrait être combinés à d'autres vaccins muqueuxMucosal vaccination, especially intranasal administrated ones, has been considered to be ideal for protection from pathogens invading through mucosal sites. However, the lack of specific adjuvant and insufficient acknowledgement of nasal immune system limits the development of vaccine. P1, a conserved region of gp41 envelope glycoprotein, was recently developed into a prophylactic HIV-1 vaccine immunized via both the intramuscular and intranasal routes. It showed high efficiency in pre-clinical and phase I clinical trial due to induction of P1 specific mucosal IgA with transcytosis blocking activity and IgG inducing antibody dependent cell cytotoxicity. In this study, we characterized the immunological mechanism underneath P1-vaccine in nasal mucosa. Firstly, we demonstrated that P1 initiate immune responses by inducing nasal epithelial cells to secret the Th2 cytokine Thymic Stromal LymphoPoietin (TSLP). TSLP has been reported to be a strong mucosal adjuvant, and its receptor TSLP-R plays a critical role in IgA response. We showed that P1 induce TSLP expression via the interaction with galactosyl ceramide, the receptor of HIV-1 mucosal entry. Furthermore, we identified Calcineurin/NFAT signaling pathway and microRNA-4485 as important players in the regulation of TSLP production induced by P1. Secondly, we showed that P1 modulates innate immune responses by activate dendritic cells (DCs). P1 stimulation results in enhanced expression of costimulatory molecules on DCs. Furthermore, the secretion of IL-6, IL-10 were increased, while IFN-γ was reduced, indicating that P1 activated DCs polarize into a Th2 and IgA prone phenotype. In addition, IL-8, CCL20, CCL22 were produced indicating a capacity at recruiting immune cells to mucosal surface for initiation of an adaptive immune response. MMP-9 was also produced allowing degradation of the extracellular matrix and facilitating the migration of immune cells out of the mucosa. Stricingly, a TSLP autocrine loop was observed as P1 induced DCs to secret TSLP and meanwhile, enhanced DC expression of TSLP-R. Finally, P1 activated DCs enhanced the proliferation of CD4+ T cells. In conclusion, we demonstrated that P1 is a multi-functional protein with a great interest for vaccine development, not only as an antigen for vaccine candidate, but also as a potential adjuvant that can be combined to other mucosal vaccines
9
Dantas, M?rcia Danielle de Ara?jo. « Estudo do genoma do v?rus causador da mionecrose infecciosa em camar?es e desenvolvimento de m?todos para detec??o de polimorfismos ». Universidade Federal do Rio Grande do Norte, 2014. http://repositorio.ufrn.br:8080/jspui/handle/123456789/12630.
Texte intégralRésumé :
Made available in DSpace on 2014-12-17T14:03:44Z (GMT). No. of bitstreams: 1
MarciaDAD_DISSERT.pdf: 4264187 bytes, checksum: 68a1d188a3ddcbd9b3e88211ae1a47e7 (MD5)
Previous issue date: 2014-08-01Coordena??o de Aperfei?oamento de Pessoal de N?vel Superior
Shrimp farming is one of the activities that contribute most to the growth of global aquaculture. However, this business has undergone significant economic losses due to the onset of viral diseases such as Infectious Myonecrosis (IMN). The IMN is already widespread throughout Northeastern Brazil and affects other countries such as Indonesia, Thailand and China. The main symptom of disease is myonecrosis, which consists of necrosis of striated muscles of the abdomen and cephalothorax of shrimp. The IMN is caused by infectious myonecrosis virus (IMNV), a non-enveloped virus which has protrusions along its capsid. The viral genome consists of a single molecule of double-stranded RNA and has two Open Reading Frames (ORFs). The ORF1 encodes the major capsid protein (MCP) and a potential RNA binding protein (RBP). ORF2 encodes a probable RNA-dependent RNA polymerase (RdRp) and classifies IMNV in Totiviridae family. Thus, the objective of this research was study the IMNV complete genome and encoded proteins in order to develop a system differentiate virus isolates based on polymorphisms presence. The phylogenetic relationship among some totivirus was investigated and showed a new group to IMNV within Totiviridae family. Two new genomes were sequenced, analyzed and compared to two other genomes already deposited in GenBank. The new genomes were more similar to each other than those already described. Conserved and variable regions of the genome were identified through similarity graphs and alignments using the four IMNV sequences. This analyze allowed mapping of polymorphic sites and revealed that the most variable region of the genome is in the first half of ORF1, which coincides with the regions that possibly encode the viral protrusion, while the most stable regions of the genome were found in conserved domains of proteins that interact with RNA. Moreover, secondary structures were predicted for all proteins using various softwares and protein structural models were calculated using threading and ab initio modeling approaches. From these analyses was possible to observe that the IMNV proteins have motifs and shapes similar to proteins of other totiviruses and new possible protein functions have been proposed. The genome and proteins study was essential for development of a PCR-based detection system able to discriminate the four IMNV isolates based on the presence of polymorphic sites
A carcinicultura ? uma das atividades que mais contribui para o crescimento da aquicultura mundial. Entretanto, esta atividade vem sofrendo perdas econ?micas significativas devido ao surgimento de doen?as virais como a Mionecrose Infecciosa (IMN). A IMN j? est? disseminada em toda regi?o Nordeste do Brasil e atingiu outros pa?ses como Indon?sia, Tail?ndia e China. O principal sintoma da doen?a ? a mionecrose, que consiste na necrose dos m?sculos estriados do abd?men e do cefalot?rax do camar?o. A IMN ? causada pelo v?rus da mionecrose infecciosa (IMNV), um v?rus n?o envelopado que apresenta protrus?es ao longo de seu caps?deo. O genoma viral ? formado por uma ?nica mol?cula de RNA dupla fita e possui duas Open Reading Frames (ORFs). A ORF1 codifica a prote?na principal do caps?deo (MCP) e uma poss?vel prote?na de liga??o a RNA (RBP). A ORF2 codifica uma prov?vel RNA polimerase dependente de RNA (RdRp) e classifica o IMNV dentro da fam?lia Totiviridae. Assim, o objetivo desse estudo foi estudar o genoma completo do IMNV e as prote?nas codificadas no intuito de desenvolver um sistema que identificasse diferentes isolados do v?rus com base na presen?a de polimorfismos. A rela??o filogen?tica entre alguns totiv?rus foi investigada e mostrou um novo grupo para o IMNV dentro da fam?lia Totiviridae. Dois novos genomas foram sequenciados, analisados e comparados a outros dois genomas j? depositados no GenBank. Os novos genomas foram mais semelhantes entre si do que com aqueles j? descritos. Regi?es vari?veis e conservadas do genoma foram identificadas atrav?s de gr?ficos de similaridade e alinhamentos utilizando as quatro sequ?ncias do IMNV. Esta an?lise possibilitou o mapeamento de s?tios polim?rficos e revelou que a regi?o mais vari?vel do genoma se encontra na primeira metade da ORF1 e coincide com as regi?es que possivelmente codificam a protrus?o viral, enquanto que as regi?es mais est?veis se encontraram em dom?nios conservados de prote?nas que interagem com o RNA. Al?m disso, estruturas secund?rias foram preditas para todas as prote?nas empregando diversos softwares e modelos estruturais proteicos foram calculados usando modelagens por threading e simula??es ab initio. A partir dessas an?lises foi poss?vel observar que as prote?nas do IMNV possuem motivos e formas similares ?s prote?nas de outros totiv?rus, e novas poss?veis fun??es proteicas foram propostas. O estudo do genoma e das prote?nas foi essencial para o desenvolvimento de um sistema de detec??o baseado em PCR capaz de discriminar os quatro isolados do IMNV com base na presen?a de s?tios polim?rficos
10
Ramirez, Christina J. « BRCA genes : conserved regions and the potential effect of missense changes / ». Thesis, Connect to this title online ; UW restricted, 2005. http://hdl.handle.net/1773/5052.
Texte intégral
11
Baek, Daehyun. « Characterization of evolutionarily conserved mammalian alternative splicing and alternative promoters / ». Thesis, Connect to this title online ; UW restricted, 2007. http://hdl.handle.net/1773/8036.
Texte intégral
12
Choudhuri, Jomuna Veronica. « Bioinformatics approaches to large scale genome comparison, including the identification of conserved noncoding regions ». [S.l. : s.n.], 2003. http://deposit.ddb.de/cgi-bin/dokserv?idn=968573630.
Texte intégral
13
Moffet, Matthew Durwin. « Identifying regions of conserved synteny between pea (Pisum spp.), lentil (Lens spp.), and bean (Phaseolus spp.) ». Thesis, Montana State University, 2006. http://etd.lib.montana.edu/etd/2006/moffet/MoffetM1206.pdf.
Texte intégralRésumé :
The identification of conserved synteny in legumes can facilitate many different types of gene discovery. Techniques like marker assisted selection and the candidate gene approach can benefit greatly by identifying conserved synteny and genes located within those regions. Both Pisum and Phaseolus have detailed linkage maps, but a limited number of markers have been located in both species. In the present study I mapped 21 genes in Phaseolus vulgaris, 16 of which had already been located on the Lens and Pisum sativum linkage maps, the markers were used to look for conserved synteny between Pisum, Lens and Phaseolus. In particular, I was able to target marker/gene-rich regions of pea linkage groups V and VII, as well as pea linkage group III, with Pisum STS markers and universally designed gene-specific markers already located on the pea linkage map. About 50% of the tested genes amplified an appropriate sized fragment in Phaseolus, but less than 40 % of the gene-specific markers showed polymorphism by cleaved amplified polymorphic sequence (CAPS) analysis in bean. The data reveals little evidence for extensive gene order conservation, and even some closely linked (<5cM) loci in Pisum are not linked in Phaseolus vulgaris. The only example of conserved synteny was approximately 15cM on pea and lentil linkage group V and bean linkage group 1. Paal, Enolase, and TufM were first identified in the syntenic area and allowed identification of fin/det, one of several TFL genes already mapped in bean, as another orthologous loci between pea and bean. Finding conservation of synteny with Paal, identified Paal3 and TFL1 genes as linked loci in Arabidopsis thaliana on linkage group 5. The pea locus Paal1,2 is then speculated to be a tandem duplication of a Paal3 homolog in a ancient common ancestor and probably occurring after the speciation of Pisum.
14
Campanera, Reig Mireia. « ¿Para quién se conserva la laguna Jacinto ? Conflictividad socioambiental en el Bajo Marañón, Amazonía peruana ». Doctoral thesis, Universitat de Barcelona, 2016. http://hdl.handle.net/10803/398394.
Texte intégralRésumé :
Unas jornadas de pesca en la laguna Jacinto (Reserva Nacional Pacaya Samiria, Perú) en 2009, evidenciaron un conflicto latente entre distintas formas de concebir, estar e intervenir en un área natural protegida amazónica y en una laguna en particular. Situación que representa a su vez las contradicciones y encrucijadas en que se hallan dos modelos socioambientales que conviven en esta área protegida, el desarrollo sostenible y el que aquí se denomina cuidado – un modelo local -.
La tesis doctoral aborda el estudio de las jornadas de pesca a partir de la identificación y análisis de cada agente social implicado. Por parte del Estado están la Jefatura de la Reserva Nacional Pacaya Samiria y la Dirección Regional de Producción. Como agente del desarrollo sostenible está la Agencia Española de Cooperación Internacional al Desarrollo. Y en el ámbito local, la comunidad de San Jacinto, el grupo de pesca Tigres Negros y desde su perspectiva, la Boa de la laguna (ser no humano con intencionalidad reconocida). El estudio revela como cada uno de ellos tiene propósitos, vínculos y representaciones distintas respecto la laguna. Por lo que todos ellos tratan de posicionarse desde su propia y compleja perspectiva en este escenario lacustre heterogéneo.
Esta tesis analiza la cultura acuática y pesquera de San Jacinto y la zona del bajo Marañón, desde una perspectiva histórica, política y cultural. Hecho que ha permitido comprender la complejidad de la conflictividad socioambiental latente que se expresa en el interior de la Reserva Nacional Pacaya Samiria.A few days of fishing in 2009 reveal a latent conflict in the Jacinto lagoon (Pacaya Samiria National Reserve, Peru), raising different ways of conceiving, being, and intervening in the protected area and the lagoon. This situation is the consequence of the contradictions and dilemmas of two socio-environmental models: the sustainable development model and the local model of 'cuidado'. This research identifies and analyzes every agent involved in the fishing activity. First of all, the state institutions are the Direction of the Pacaya Samiria National Reserve and the Regional Department of Production. Second, the Spanish International Agency for Cooperation and Development (AECID). The first and the last one are a good example of the sustainable development agents. At the local level, there are three agents: the citizens of the San Jacinto community, the fishers of the organization called ‘Tigres Negros', and the Snake of the lake (a non-human being with recognized intention, from the local perspective). The conclusion shows that each agent has its relations, representations, and agenda around the lagoon. Thus, every agent takes its particular and complex position in this heterogeneous aquatic space. With a historical, political and cultural perspective, this doctoral dissertation analyzes the aquatic and fishery culture of San Jacinto and the low Marañón area. This case study contributes to understanding the complexity of the latent social and environmental conflict within the Pacaya Samiria National Reserve.
15
GUYOT, JEAN-BAPTISTE. « Mutagenese dirigee des regions conservees de l'adenine adn methylase d'e. Coli (dam) ». Paris 6, 1994. http://www.theses.fr/1994PA066141.
Texte intégralRésumé :
La methylase dam (dna-adenine-metylase) d'e. Coli reconnait les sites gatc sur l'adn et transfere le groupement methyl de la s-adenosyl-methionine sur le groupement amino des adenines de ces sites. La sequence primaire d'acides amines de la methylase dam presente de fortes homologies avec celles de la methylase dam de t4, de m. Dpnii (qui methylent egalement la sequence gatc sur l'adn) et de m. Ecorv (qui methyle la sequence gatatc). La zone iii, commune a ces enzymes, a ete proposee comme participant a la reconnaissance de l'adn. La methylase dam d'e. Coli possede d'autres part une autre zone d'homologie, la zone iv, qui contient le motif (d, n, s), ppy, present dans toutes les n6-adenine et n4-cytosine mtases. Nous avons realise une mutagenese dirigee dans ces deux zones d'homologie afin de preciser leurs roles fonctionnels. Les mutants obtenus, testes pour la fixation de la s-adenosyl-methionine et la liaison a l'adn, soulignent l'importance de la zone iv dans le processus de methylation. Par ailleurs, nous avons etudie la validite statistique des alignements proposes pour les sequences d'acides amines des methylases. Cette etude nous a permis d'invalider un mecanisme propose d'evolution des methylases par duplication genique. D'autre part, nous avons pu confirmer la parente des enzymes de la famille dam
16
FERNANDES, MARIE. « Etude comparative de deux regions chromosomiques conservees au cours de l'evolution : la bande q13 du chromosome 11 humain et la region pericentromerique du chromosome 19 de la souris ». Aix-Marseille 2, 1997. http://www.theses.fr/1997AIX22059.
Texte intégralRésumé :
La comparaison des genomes permet non seulement d'etudier la phylogenie des especes mais egalement d'identifier des genes impliques dans des processus biologiques conserves au cours de l'evolution. Les approches moleculaires comparatives peuvent etre menees chez les organismes complexes a trois niveaux de resolution : la cytogenetique, la cartographie et la sequence des macromolecules (adn, proteines). Nos travaux concernent la cartographie physique comparative de deux regions chromosomiques homologues entre l'homme et la souris : la bande q13 du chromosome 11 humain (hsa11q13) et la region pericentromerique du chromosome 19 de la souris (mmu19). La region hsa11q13 est associee a plusieurs maladies et a divers cancers humains. Par ailleurs, des loci mutes dans diverses pathologies murines ont ete localises dans la region pericentromerique de mmu19. Notre but a ete de definir le degre d'homologie entre ces deux regions chromosomiques afin d'exploiter cette conservation de la syntenie pour l'identification de genes alteres dans les pathologies humaines ou murines. Pour cela, nous avons dans un premier temps localise precisement sur hsa11q13 les zones distales et proximales de rupture de conservation syntenique et estime la taille totale de la region d'homologie avec mmu19 a environ 16 mb. Dans un deuxieme temps, nous avons etabli une cartographie physique hautement resolutive dans la region pericentromerique de mmu19. Plusieurs approches ont ete combinees : la cartographie de restriction a grande echelle par pfge, l'etablissement de continuum de yacs, l'analyse d'hybrides somatiques et l'hybridation in situ sur chromosomes metaphasiques. De nouvelles stss ont ete isolees et cartographiees ; plusieurs orthologues de genes de hsa11q13 ont ete localises dans la region pericentromerique de mmu19. Deux cartes physiques a haute resolution de 0,9 et 2,5 mb ont ete obtenues et orientees. L'integration de marqueurs genetiques et de genes (conserves entre les especes) sur ces cartes nous a permis de les comparer respectivement avec les cartes genetiques de mmu19 et les cartes physiques prealablement obtenues sur hsa11q13. Ce travail a non seulement contribue a la cartographie physique de mmu19, mais a egalement permis de mettre en evidence, entre autres, une rupture de conservation de liaison avec le genome humain et des distances intergeniques relativement bien conservees entre l'homme et la souris.
17
Pereira, Ryan Apolinario. « FUNCTIONAL ANALYSIS OF TWO CONSERVED REGIONS OF ESCHERICHIA COLI ELONGATION FACTOR G AS STUDIED BY SITE-DIRECTED MUTAGENESIS ». The Ohio State University, 2002. http://rave.ohiolink.edu/etdc/view?acc_num=osu1039030876.
Texte intégral
18
Pereira, Ryan A. « Functional analysis of two conserved regions of Escherichia coli elongation factor G as studied by site-directed mutagenesis / ». The Ohio State University, 2002. http://rave.ohiolink.edu/etdc/view?acc_num=osu1486549482669521.
Texte intégral
19
JACQUET, PARNAUDEAU MARIE-ANGE. « Etude comparative de promoteurs d'e. Coli naturels et mutes dans les regions non conservees ». Paris 7, 1987. http://www.theses.fr/1987PA077120.
Texte intégral
20
Hing, Benjamin. « Investigating differential regulation of BDNF promoter IV activity by upstream polymorphic evolutionary conserved regions : implications for mood disorders and cognitive disfunction ». Thesis, University of Aberdeen, 2011. http://digitool.abdn.ac.uk:80/webclient/DeliveryManager?pid=185597.
Texte intégralRésumé :
Major depressive disorder (MDD) and bipolar disorder (BD) are psychiatric diseases that affect behavior and impair cognition. A gene important to these disorders is the brain derived neurotrophic factor (BDNF) which is involved in processes controlling neuroplasticity. Previous studies have suggested that BDNF expression levels have to be finely regulated for normal mental health and cognition. This study therefore aimed to identify cis-regulatory elements that regulate BDNF promoter IV (BP4), which plays a role in mood and cognition, and investigated how polymorphisms in these cis-regulatory elements might alter BP4 activity contributing to MDD and BD. BP4-LacZ transgenic mice and primary neuron cultures were used to show that BP4 was active in the hippocampus, cortex and amygdala and responded to PKC, KCl and Wnt signaling activation. Using comparative genomics, two highly conserved regions were identified, BE5.1 and BE5.2, which contain the rs10767664 and rs12273363 polymorphisms respectively. Reporter gene assays in primary cultures derived from these brain structures showed that BE5.1 and BE5.2 were responsible for “filtering” or “gating” the effects of different combination of activated signal transduction pathways on BP4. Thus, BE5.1 increased BP4 response to forskolin in cortical cultures while abolishing BP4 response to PMA in hippocampal cultures. Similarly, BE5.2 permitted BP4 response to KCl and combined forskolin and PMA treatment, but not individual forskolin and PMA treatment nor LiCl in cortical cultures. Significantly, the minor allele of rs12273363, which has been associated with MDD and BD susceptibility, acted as a more potent repressor of BP4 response to neuron depolarization by KCl and PKA/PKC activation in different primary cultures. The possible relevance of these findings to the role of altered BDNF expression in MDD and BD are discussed.
21
Danchin, Etienne Gaëtan Jacques. « Reconstruction of ancestral genomic regions by comparative analysis of evolutionary conserved syntenies : Towards reconstructing the genome of the ancestor of all Bilaterian species (Urbilateria) ». Aix-Marseille 2, 2004. http://www.theses.fr/2004AIX22070.
Texte intégral
22
Barrantes, Dávila Samuel Alexander, et Samillán José Alexander Vidaurre. « Proyecto de preinversión para la instalación de una planta de procesamiento y comercialización de conservas de pescado en la región Lambayeque ». Bachelor's thesis, Universidad Católica Santo Toribio de Mogrovejo, 2018. http://tesis.usat.edu.pe/handle/usat/1042.
Texte intégralRésumé :
Las conservas de pescado en la actualidad brindan al consumidor una mayor garantía de calidad y salud, para así sentirse seguros, porque al momento de ser adquirido, ellos no deben de tener ninguna duda de la procedencia del producto, pues este cuenta con normas y certificaciones internacionales por lo que garantizan su proceso productivo. El presente trabajo de investigación se ha desarrollado con la finalidad de determinar la viabilidad del proyecto de Inversión para la Instalación de una Planta Procesadora y Comercializadora de Conservas de Pescado en la Región Lambayeque, con la intención de atender al mercado Lambayecano y a todas las zonas del país, con un producto de confianza y calidad para el buen consumo. El presente proyecto de inversión es de tipo descriptivo, porque se medirán las variables en estudio y retrospectivo, porque se trabajaron con hechos que se dieron en la realidad; es decir de registros o información secundaria. Se estudia las situaciones, costumbres y actitudes predominantes a través de la descripción exacta de las actividades, objetos, procesos y personas; cuyo objetivo es determinar la viabilidad estratégica, la viabilidad de mercado, la viabilidad técnica, la viabilidad ambiental, la viabilidad administrativa y la viabilidad económico financiero. Se determinó mediante la investigación que la evaluación económica financiera del proyecto es viable por haber obtenido una Tasa Interna de Retorno Económico (TIRE) de 29.2% y un Valor Actual Neto Económico (VANE) de US$ 2, 006,170.74 de dólares; lo que nos permite considerar a este proyecto un atractivo negocio para invertir.Tesis
23
Salazar, Rondon Maria Claudia [Verfasser], Jane E. [Gutachter] Parker et Alga [Gutachter] Zuccaro. « Role of evolutionary conserved MAP kinase C-terminal regions in transcriptional activation in Arabidopsis thaliana / Maria Claudia Salazar Rondon ; Gutachter : Jane E. Parker, Alga Zuccaro ». Köln : Universitäts- und Stadtbibliothek Köln, 2019. http://d-nb.info/1213023629/34.
Texte intégral
24
Golin, Raíssa Ochôa. « Estudo da Evolução da Protease 3c de Picornaviridae e Vírus Picorna-like Através da sua Sequência Proteica e Domínios Conservados ». Universidade Federal do Pampa, 2014. http://dspace.unipampa.edu.br:8080/xmlui/handle/riu/213.
Texte intégralRésumé :
Submitted by Sandro Camargo (sandro.camargo@unipampa.edu.br) on 2015-05-07T22:43:52Z
No. of bitstreams: 1
126110038.pdf: 2182930 bytes, checksum: 1d0e56324e775d985abbaf5cea8f4038 (MD5)Made available in DSpace on 2015-05-07T22:43:52Z (GMT). No. of bitstreams: 1 126110038.pdf: 2182930 bytes, checksum: 1d0e56324e775d985abbaf5cea8f4038 (MD5) Previous issue date: 2014-03-21
As abelhas apresentam uma combinação de características individuais e ainda de cooperação animal não encontrada no restante do reino animal. São insetos sociais e participam da polinização de diversas plantas que fornecem alimento para o homem. No Brasil com a africanização das abelhas, essas tornaram-se altamente produtoras e enxameadoras, o que vem tornando o país uma potência na produção de mel e outros produtos originados da atividade apícola. Muitas doenças podem afetar as abelhas, dentre elas muitas causadas por vírus. Controlar as infecções virais é essencial para a manutenção ecológica das abelhas e da produção apícola. Ao mesmo tempo, existe a possibilidade de relacionar vírus que infectam humanos com os vírus que infectam as abelhas, visto que os tratamentos utilizados para os seres humanos poderiam ser utilizados em colméias e, ao mesmo tempo, utilizar as abelhas como modelo de estudo para o desenvolvimento de novos antivirais. Na busca por um ponto em comum analisamos filogeneticamente a protease 3C, que ocorre nos vírus da super-família Picorna-like, onde encontram-se os vírus que parasitam as abelhas. Essa protease tem a capacidade de clivar a poliproteína viral nas proteínas maduras do vírus e ainda causar a degradação proteolítica das proteínas do hospedeiro. Até hoje não foi encontrada uma forma de utilizar a protease 3C em estudos filogenéticos pois existe muita divergência das suas sequências entre os vírus. O objetivo dessa pesquisa foi identificar uma forma de analisar filogeneticamente a protease 3C. As sequências da protease 3C e da RdRp de 55 vírus foram coletadas do NCBI ( National Center of Biotechnology Information) e submetidas ao MEME ( Multiple Em for Motif Elicitation), onde foram obtidos quatro sítios conservados. Após foi realizada a análise filogenética dos sítios conservados por Máxima Verossimilhança e análise da distância entre os sítios por parcimônia e ainda foi construída uma árvore com base na RdRp. As árvores dos sítios 1 e 2 apresentaram uma melhor robustez estatística e agrupamento dos vírus. Essas regiões conservadas da protease 3C-Pro podem ser o início para estabelecermos uma relação entre as proteases dos picornavírus e vírus picorna-like na busca da compreensão do seu mecanismo de infecção viral e também uma alternativa de estudo para outras sequências com alta variabilidade. O uso dos domínios 1 e 2 proporcionou a árvore com maior robustez apresentada até o dia de hoje para esta proteína viral.
The bees have a combination of individual features and animal cooperation is not yet found in the rest of the animal kingdom . They are social insects and participate in the pollination of many plants that provide food for man . In Brazil with the africanization of bees , these have become highly producing and swarm , which is making the country a power in the production of honey and other products derived from beekeeping . Many diseases can affect bees , among them many caused by viruses . Control viral infections is essential for ecological maintenance of bees and beekeeping . At the same time , it is possible to relate viruses that infect humans and viruses that infect the bees , whereas the treatments for humans could be used in beehives and at the same time using the bees as a model for development of new antiviral agents. In the search for a common point analyzed phylogenetically 3C protease , which occurs in the superfamily Picorna -like, which are viruses that parasitize bees virus. This protease is capable of cleaving the polyprotein, the mature viral proteins and viruses also cause the proteolytic degradation of host proteins . Until today there a way to use the 3C protease was found in phylogenetic studies because there is much divergence of their sequences between virus.The objective of this research was to identify a way to analyze phylogenetically 3C protease . The 3C protease and RdRp sequences of 55 viruses were collected from the National Center for Biotechnology Information , submitted to MEME , where four conserved sites were obtained . Upon phylogenetic analysis of the conserved sites and by maximum likelihood analysis of the distance between sites by parsimony was performed and was still a tree constructed based on the RdRp . Trees of sites 1 and 2 had a better statistical robustness and clustering of virus. These conserved regions of the 3C protease - Pro may be the start to establish a relationship between the proteases of the picornavirus and Picorna-like viruses in the quest to understand the mechanism of viral infection and also an alternative study for other sequences with high variability . The use of domains 1 and 2 provided the tree with greater robustness displayed until today for this viral protein.
25
Cabral, Byrne Pablo Enrique, et Pavlich Pablo Antonio José Arnillas. « Analizar la viabilidad de exportar alcachofa fresca congelada, corazones y fondos en conserva, desde la Región Junín, al mercado norteamericano ». Master's thesis, Universidad Peruana de Ciencias Aplicadas (UPC), 2013. http://hdl.handle.net/10757/273834.
Texte intégralRésumé :
Estados Unidos y países europeos realizan una activa intervención estatal en el desarrollo de sus sectores agrícolas a través de los diferentes subsidios existentes. Como existía una demanda que no era satisfecha con la oferta habida y nuevos productos que no habían en el país importador, surgía la necesidad de importar productos; pero como los precios de los mismos eran elevados no había forma de introducirlos; es por ello que nacen diversos acuerdos comerciales que brindan beneficios arancelarios permitiendo exportar e importar productos a precios muy competitivos. Debido a que el ATPDEA y el TLC con los Estados Unidos (falta por ratificar por el congreso norteamericano) otorgan beneficios arancelarios por diversos productos en los cuales se considera a la alcachofa, el presente proyecto tiene por finalidad evaluar la exportación de fondos y corazones encurtidos y alcachofa fresca al mercado norteamericano que representaron en el período 2000-2005 el 0.20% (34 millones de US$) del total de las exportaciones peruanas a EEUU, el 0.51% del total de las exportaciones peruanas realizadas en el sector no tradicional a EEUU, el 2.75% del total de las exportaciones peruanas realizadas en el sector agropecuario y agroindustrial a EEUU. Estos productos se estarían exportando sin marca a los agentes de venta o distribuidores localizados en California. Se ha seleccionado como mercado meta objetivo al 56% de la población blanca de California entre los 15 y más años de edad quienes siempre reemplazan la carne por frutas y verduras. En promedio (2007-2011) representarán 1.35 millones de habitantes por año. Considerando un consumo per cápita de 0.22krs, la cantidad demandada total (2007-2012) sería de 1,481 toneladas métricas, pero las ventas proyectadas que se han considerado y que se estaría exportando sería de 980 toneladas métricas (560 TM de alcachofa fresca sin espinas y 420 TM de corazones y fondos). El valor FOB del frasco de 220grs en promedio sería de S/.1.62 y por la bolsa de 6 alcachofas fresca S/.3.77, dando un ingreso total (2008-2012) de S/.10,153,496 por el total de frascos y bolsas, cuyo costo total de producción es de S/.7,424,549, que es el mismo costo de ventas. El gasto administrativo total sería de S/.1,107,418 el gasto total de ventas de S/.316,045, el gasto financieros de S/.1,030,037, la depreciación de S/.873,933 y por impuesto a la renta de S/.30,358, obteniendo una pérdida neta de S/.516,794 soles (-5% sobre las ventas), con lo cual no se alcanza la utilidad esperada por los accionistas (20%). Para el análisis proyectado de 5 años en el flujo de caja libre se ha calculado un WACC de 15.46%, obteniendo un VAN de -S/.2,313,944 y un ROI de 6.71% (no cumple con el 20% esperado) y un EVA de -S/.136,402 en el 2008 con lo cual no se hace viable la implementación del mismo.Tesis
26
MARIE-JEANNE, TORDO VERONIQUE. « Region 5 du genome du virus y de la pomme de terre : etude par sequencage de son polymorphisme et des motifs conserves. contribution a l'etude de la proteine p1 ». Paris 11, 1993. http://www.theses.fr/1993PA112434.
Texte intégralRésumé :
Le virus y de la pomme de terre (pvy) est le membre type des potyvirus. Son genome est constitue d'un arn simple brin d'environ dix mille nucleotides. La region 5 non codante et le cistron codant pour la proteine p1 sont contigus et constituent un dixieme du genome viral. Nous avons clone ces deux regions pour huit souches de pvy d'origine geographique differente et presentant une gamme d'hotes et une symptomatologie variees. Afin d'etudier le polymorphisme et de reperer des motifs conserves importants au niveau de ces deux regions, nous avons sequence les huit souches au niveau de la region 5 non codante et cinq d'entre elles au niveau de la region codant pour la proteine p1. Nos sequences, jointes a quatre sequences publiees dans la litterature ont ete alignees avec le programme pile-up. Au niveau de la region 5 non codante, deux motifs ressortent qui pourraient etre fonctionnellement importants: uuuca et (caa)n. Par analogie avec leur role etabli dans d'autres genomes viraux, ces motifs pourraient intervenir dans l'initiation ou l'activite activatrice de la traduction. Le dendrogramme deduit de l'alignement multiple repartit les souches en trois groupes dont un se detache: il contient les souches necrogenes sur tubercules d'emergence recente ainsi qu'une souche non necrogene. Au niveau de la proteine p1 (proteine de point isoelectrique 10,9) nous avons identifie des motifs potentiellement impliques dans la liaison a l'arn. Afin de tester in vitro ces differents motifs nous avons clone et exprime la proteine p1 dans e. Coli. Cette expression nous a permis de preparer un serum contre la proteine p1. Le dendrogramme etabli sur le pourcentage de similarite en acides amines repartit les souches de la meme facon que precedemment
27
Galliot, Sonia. « A la recherche de nouvelles AgNORs : une famille de protéines nucléolaires conservées et marqueurs potentiels du cancers ». Doctoral thesis, Universite Libre de Bruxelles, 2010. http://hdl.handle.net/2013/ULB-DIPOT:oai:dipot.ulb.ac.be:2013/210190.
Texte intégralRésumé :
Comme le nucléole joue un rôle fondamental dans l’expression des protéines, via la synthèse des ARN ribosomiques, il n’est donc pas surprenant que des études aient révélé un lien étroit, entre des dysfonctionnements nucléolaires et l’origine de certaines maladies humaines. La découverte, il y a plusieurs années, d’un taux anormalement élevé de protéines nucléolaires dites argyrophiles ou AgNORs, dans les cellules tumorales, a permis d’envisager leur utilisation comme outil diagnostique ou pronostique du cancer. Détectées, de manière in vitro grâce à leur affinité pour l’argent, l’identification de quelques protéines AgNORs n’a pourtant pas permis d’établir une caractéristique commune à toutes les protéines argyrophiles détectées dans les extraits nucléolaires. Ainsi, bien que le test colorimétrique AgNOR soit utilisé dans de nombreux laboratoires académiques, l’absence d’identification de protéines AgNORs spécifiques du processus de cancérisation, a limité son utilisation en laboratoire clinique. Comme certaines limites technologiques et expérimentales ont limité leur caractérisation chez l’humain, nous avons donc décidé de reprendre les recherches sur ce sujet et de le réactualiser grâce aux avancées technologiques et scientifiques. Les protéines AgNORs étant étroitement liées à la biogenèse des ribosomes, nous avons donc décidé d’amorcer nos recherches chez la levure Saccharomyces cerevisiae, dans laquelle, la voie de biosynthèse des ribosomes a été particulièrement bien décrite. Devant l’intérêt biologique et médical de ces protéines, l’objectif de ce projet a donc été triple :1-identifier des protéines AgNORs chez la levure
2-caractériser les propriétés physico-fonctionnelles et physico-chimiques de ces protéines AgNORs.
3-utiliser ces caractéristiques physico-chimiques pour rechercher de nouvelles AgNORs humaines, spécifiques de processus de cancérisation et potentiellement utilisables comme marqueurs tumoraux./The nucleolus is a subnuclear compartment that organized around ribosomal gene (rDNA) repeats NORs, which encode for ribosomal RNA. A peculiar group of acidic proteins which are highly argyrophilic are also localized at the same sites as NORs, thus allowing NORs to be very clearly and rapidly visualized by silver nitrate staining procedures. However, if three human argyrophilic proteins, UBF, C23 (nucleolin) and B23 (nucleophosmin), have been associated for staining of NOR, the exact number of AgNOR proteins and their intrinsic biochemical feature are unclear. Here, we have performed an heterologous screen in a genetically tractable eukaryotic organism (budding yeast) for the identification of novel AgNOR proteins and in vitro characterized an intrinsic feature that underlies silver binding and offers a strong predictive value for the identification of novel human AgNOR proteins.
Doctorat en Sciences
info:eu-repo/semantics/nonPublished
28
Pican?o, Jos ? Reinaldo Alves. « Desenvolvimento, sustentabilidade e conserva??o da biodiversidade na amaz?nia : a produ??o familiar agroextrativista em ?reas protegidas no sul do amap ? » Universidade Federal do Rio Grande do Norte, 2010. http://repositorio.ufrn.br:8080/jspui/handle/123456789/13731.
Texte intégralRésumé :
Made available in DSpace on 2014-12-17T14:20:16Z (GMT). No. of bitstreams: 1
JoseRAP_TESE_1-191.pdf: 2035347 bytes, checksum: c662b0321ff9a645d1e341dd4552caca (MD5)
Previous issue date: 2010-12-04The establishment of Extractivism and Sustainable Development Reserves comes from an amazon forestry people resistance initiative. It means an option of natural resources management as protected areas for agroextractivism purposes. According to the institutional point of view, these lands, called Conservation Unity for Sustainable Exploration, belong to the government which grants the usufruct rights to the agroextractivist families under a sharing territory administration agreement among government and rural communities. The main roles of these lands are both: to improve the dwellers wellbeing, and protecting the local biodiversity. Additionally, they also represent the start of this thesis theme entitled Development, sustainability, and biodiversity conservation in the Amazon region: the use of protected areas for agroextractivism domestic yield in south of Amap? state with the objective of analyzing the performance that each territory has been reaching in terms of the attributions proposed at the beginning, when they were created. Social, economics, and environment changes that occurred in the agroextractivist areas have been evaluated from two selected test sites, named Rio Cajari Extractivist Reserve and Rio Iratapuru Sustainable Reserve, both, localized in the south of Amap? state
A cria??o de Reservas Extrativistas e Reservas de Desenvolvimento Sustent?vel, surgem a partir do movimento de resist?ncia dos povos da floresta amaz?nica, e representa uma alternativa de gest?o dos recursos naturais sob a forma de ?reas protegidas destinadas ao agroextrativismo. Do ponto de vista institucional, esses espa?os territoriais s?o Unidades de Conserva??o de Uso Sustent?vel, pertencentes ao poder p?blico, que concede o direito de usufruto ?s fam?lias agroextrativistas, num processo gest?o compartilhada desses territ?rios entre o poder p?blico e as representa??es comunit?rias. Essas ?reas t?m duplo objetivo, promover a melhoria das condi??es de vida dos moradores e garantir a prote??o da biodiversidade local. Esses objetivos constituem o ponto de partida desta tese Desenvolvimento, sustentabilidade e conserva??o da biodiversidade na Amaz?nia: a produ??o familiar agroextrativista em ?reas protegidas no sul do Amap?, que busca analisar em que medida esses territ?rios est?o cumprindo com as finalidades para as quais foram criados. A pesquisa foi realizada na Reserva Extrativista do Rio Cajari e na Reserva de Desenvolvimento Sustent?vel do Rio Iratapuru, localizadas no sul do estado do Amap?, analisando as mudan?as sociais, econ?micas e ambientais, ocorridas nessas ?reas agroextrativistas
29
Silva, Sandra Cristina Patrício da. « O que o estado português quis conservar : a avaliação e aquisição de documentos de arquivo em Portugal nos séculos XIX e XX ». Master's thesis, Universidade de Évora, 2011. http://hdl.handle.net/10174/14829.
Texte intégralRésumé :
Esta dissertação procura identificar os desígnios que orientaram as decisões do
Estado português em relação à aquisição de documentos de arquivo, com o objectivo de
verificar se esses desígnios se formalizaram numa política de avaliação e aquisição de
documentos de arquivo coerente e sistemática. A análise incidiu no Arquivo Nacional e nos
arquivos distritais durante o período cronológico que abrange o século XIX e a primeira
metade do século XX. Partindo da discussão teórica presente nos discursos de arquivistas
e investigadores, da evolução das práticas no Arquivo Nacional e das incorporações
realizadas nos arquivos distritais, esta tese defende que existiu uma visão constitutiva dos
arquivos enquanto repositórios documentais da memória da nação. No entanto, esta visão
não se concretizou numa política arquivística articulada e estrutural; ABSTRACT:This dissertation aims to identify portuguese state’s goals that guided its intervention
on acquisition of archival records. Our purpose is to verify if those goals meant a coherent
and systematic appraisal and acquisition policy. Our analysis took as object Portugal’s
national and regional archives from nineteenth to twentieth century’s first half. Beginning
from theoretical discussion that can be seen on archivists and investigators speeches,
National Archive’s practices and acquisitions occurred in regional archives, this thesis
sustains that there was a vision on the archives as national memory documental
repositories. However, this vision was not translated on an articulated and structured archival policy.
30
Park, Jung Hee. « Crystal structure of ligand-free G-protein-coupled receptor opsin ». Doctoral thesis, Humboldt-Universität zu Berlin, Mathematisch-Naturwissenschaftliche Fakultät I, 2010. http://dx.doi.org/10.18452/16049.
Texte intégralRésumé :
Rhodopsin ist als Sehpigment der Photorezeptorzellen einer der am aktivsten untersuchten GPCRs. Es besteht aus dem Apoprotein Opsin und dem inversen Agonisten 11-cis-Retinal. Der inaktivierende Ligand ist in der sieben Transmembran- Helix (TM)-Struktur des Rezeptors kovalent gebunden und muss durch Licht cis/trans-isomerisiert werden, um den Rezeptor zu aktivieren. Der aktivierte Rezep-tor katalysiert den Nukleotidaustausch im G-Protein und zerfällt innerhalb von Minuten in Opsin und all-trans-Retinal. Das visuelle Pigment wird dann durch erneute Beladung des Opsins mit 11-cis-Retinal wieder hergestellt. In der vorliegenden Arbeit wird die erfolgreiche Kristallisation des nativen Opsins aus der Stäbchenzelle der Rinderretina und die Bestimmung der Proteinstruktur bei 2.9 Å Auf-lösung dargestellt. Im Vergleich zur bekannten Struktur des inaktiven Rhodopsins zeigt Opsin deutliche Strukturänderungen in den konservierten E(D)RY und NPxxY(x)5,6F Regionen und in TM5-TM7. Auf der intrazellulären Seite ist TM6 ca. 6-7 Å nach außen gekippt, während die TM5 Helix verlängert und näher zu TM6 verschoben ist. Durch die strukturellen Änderungen, von denen einige einem aktiven GPCR Zustand zugeschrieben werden können, wird die leere Retinalbindungstasche reorganisiert, um zwei Öffnungen für Aus- und Eintritt von Retinal bereitzustellen. Die Struktur von Opsin liefert neue Erkenntnisse zur Bindung von hydrophoben Liganden an GPCRs, zur GPCR-Aktivierung und zur Signalübertragung auf das G-Protein.Rhodopsin as the visual pigment in photoreceptor cells is one of the most actively studied GPCRs. It consists of the apoprotein opsin and the inverse agonist, 11-cis-retinal. The inactivating ligand is bound in the seven-transmembrane helix (TM) bundle and cis/trans-isomerized by light to activate the receptor. The active receptor state is capable of catalyzing nucleotide exchange in the G protein and decays within minutes into opsin and all-trans-retinal. The visual pigment is then restored by reloading opsin with new 11-cis-retinal. In the present work, the successful crystallization of native opsin from bovine retinal rod cells and determination of the protein structure to 2.9 Å resolution is presented. Compared with the known structure of inactive rhodopsin, opsin displays prominent structural changes in the conserved E(D)RY and NPxxY(x)5,6F regions and TM5-TM7. At the cytoplasmic side, TM6 is tilted outwards by 6-7 Å, whereas the helix structure of TM5 is more elongated and close to TM6. These structural changes, of which some are attributed to an active GPCR state, reorganize the empty retinal binding pocket to disclose two openings for exit and entry of retinal. The opsin structure thus sheds new light on binding of hydrophobic ligands to GPCRs, GPCR activation and signal transfer to the G protein.
31
Gerhardt, Cleyton Henrique. « Pesquisadores, popula??es locais e ?reas protegidas : entre a instabilidade dos lados e a multiplicidade estrutural das posi??es ». Universidade Federal Rural do Rio de Janeiro, 2008. https://tede.ufrrj.br/jspui/handle/tede/731.
Texte intégralRésumé :
Made available in DSpace on 2016-04-28T20:13:56Z (GMT). No. of bitstreams: 1
CLEYTON HENRIQUE GERHARDT.pdf: 4483893 bytes, checksum: 77861b188c8972113d990c1c5fc20130 (MD5)
Previous issue date: 2008-08-30Funda??o Carlos Chagas Filho de Amparo a Pesquisa do Estado do Rio de Janeiro
The relationship between local populations and protected areas has been an extremely controversial issue. However, this divergences also extend to the scientific domain, mobilizing the attention of scientists, who are interested both in researching specific aspects and in interfering in public policies related to this issue. If there is indeed a general agreement among specialists, then it is about the fact that the discursive context of this issue is marked by dissension, polyphony and by fierce academic dialogues. Bearing this in mind, I observed this controversial world reflected in the relationships among the scientists who, by operating in the frontiers of political action and scientific research, got involved in this debate. The thesis is divided into two parts. In the first part, some interpretative similarities and dissimilarities between authors are analysed and described based on their publications. As I intend to show, antagonisms, oppositions, divergences, but also alliances, agreements and convergences generate, within a wider strength balance marked by different identity/alterity levels, a permanently unstable and inconsistent structural environment. The second part is also divided into two distinct chapters. In the first chapter, I worked on fragments of different social trajectories and life experiences reported by 33 researchers I had the opportunity to interview, which allowed an insight into an extremely heterogeneous set regarding the paths they followed. In the last chapter, I present their observations, reflections, assessments and criticism on some aspects related to policies that target local populations and protected areas.
A rela??o entre popula??es locais e ?reas protegidas ? tema hoje extremamente controvertido no ?mbito cient?fico, mobilizando a aten??o de cientistas interessados tanto em pesquisar quest?es espec?ficas como em interferir em pol?ticas p?blicas a ele direcionadas. Se h? um consenso entre especialistas, ? que estamos diante de um contexto discursivo caracterizado pelo dissenso, pela polifonia e por ?cidos di?logos acad?micos. Diante disso, passei a observar esse universo controvertido que marca a rela??o entre cientistas que, atuando nas fronteiras da a??o pol?tica e da pesquisa cient?fica, se envolveram com este debate. Como tentei mostrar, oposi??es, diverg?ncias, mas, tamb?m, alian?as e converg?ncias geram, dentro de um equil?brio de for?as marcado por planos de identidade/alteridade distintos, um ambiente estrutural inst?vel. Dividi a tese em duas partes. Na primeira, problematizo e descrevo, a partir das suas respectivas publica??es cient?ficas, encontros e desencontros interpretativos protagonizados pelos autores. A segunda parte traz dois cap?tulos. No primeiro, trabalhei com fragmentos de diferentes trajet?rias sociais e experi?ncias de vida relatadas por 33 pesquisadores que tive a oportunidade de entrevistar, o que permitiu visualizar um quadro extremamente heterog?neo quanto ?s trilhas por eles percorridas. No ?ltimo cap?tulo apresento suas observa??es, reflex?es, avalia??es e cr?ticas sobre alguns aspectos relacionados ?s pol?ticas direcionadas ?s popula??es locais e ?reas protegidas. Ao final, al?m de apontar um inconveniente ?tico vinculado ? abordagem do estudo que realizei, reconecto alguns aspectos discutidos ao longo da tese com vistas a indicar o car?ter problem?tico que h? por tr?s da cristaliza??o de controv?rsias cient?ficas fortemente politizadas.
32
Lin, Yu-Shing, et 林育星. « Enzyme Class Prediction via Mining Conserved Region in Sequence and Structure ». Thesis, 2006. http://ndltd.ncl.edu.tw/handle/58424169935748829904.
Texte intégralRésumé :
碩士國立臺灣大學
資訊工程學研究所
94
The active sites and binding sites of the protein structure are the main working areas of the functional proteins. Based on this assessment, the qualitative and quantitative analyses of the variant characteristics of the active site and binding site are the first steps towards predicting protein functionalities. These characteristics include conformation, bio-chemical property etc. Present methods to predict protein function mostly exploit known protein-ligand complex to conduct factitious or automatic structure analysis to obtain the Motif of surrounded atoms of binding site. However, this thesis is providing a different point of view. Our assumption is though the protein function is decided by the location of active site or binding site, there should be some local conserved regions between the proteins that possess same function. In other words, these local conserved regions might not be the surrounded amino acids of binding site, but it indeed affects the structure and the way of working for active site or binding site. To describe the framework of these areas, it can’t be decided only by a single sequence or the structure analysis. What it needs is a further understanding of the relationship between sequence and structure, and takes it into consideration. To reach this goal, we developed the following steps. First, circle each residue around 10Å as a spheroid to represent a local region. Second, use each spheroid to conduct sequence and structure analysis. Third, with enzyme data bank, we can identify the belonging local conserved region of protein through same category of protein. In the future, further discussion about the relationships between theses local conserved region and the functions should be investigated.
33
Duque, Hernando. « Phenotypic characterization of three phylogenetically conserved stemloops in the Mengovirus 3 ́untranslated region ». 1998. http://catalog.hathitrust.org/api/volumes/oclc/40944597.html.
Texte intégralRésumé :
Thesis (Ph. D.)--University of Wisconsin--Madison, 1998.Typescript. eContent provider-neutral record in process. Description based on print version record. Includes bibliographical references (leaves 146-156).
34
Huang, Liang-Yin, et 黃亮尹. « Identification and Characterization of the Conserved Region 1 of Bacillus subtilis sigmaA Factor ». Thesis, 2001. http://ndltd.ncl.edu.tw/handle/39565274079948701067.
Texte intégralRésumé :
碩士國立中興大學
生物化學研究所
89
The sigma subunit of prokaryotic RNA polymerase is essential for promoter recognition and initiation of transcription. Our previous study has shown that the deletion mutant sigmaA factors, SND73- and SND94-sigmaA, are active in transcription after reconstitution with core RNA polymerase; however, SND129-sigmaA is inactive due to the loss of promoter-binding activity of the mutant sigmaA-RNA polymerase. The present study is aimed to explore how much amino acid residues in the N-terminal region of sigmaA are unnecessary for its full in vitro activity, and why further deletion from this amino acid position would cause the loss of transcription activity of the mutant sigmaA factor. Besides, we hope to obtain a series of functional sigmaA factors, which would enable us to study the crystal structure or the structural and functional relationship of sigmaA factor in the future. To fulfill this goal, 25 mutant sigmaA factors, with deletion at the N-terminus and spanning amino acid no. 74 to 127 of sigmaA, were constructed and purified. The functional properties of these mutant sigmaA factors were analyzed in vitro. Our data revealed that deletion of more than 103 amino acids at the N-terminus of sigmaA have resulted in a significant loss of the transcription activity of the reconstituted mutant sigmaA-RNA polymerases. Gel retardation assays indicated that the inactivation of transcription of these mutant sigmaA-RNA polymerases was due to the reduction of promoter-binding activity of the reconstituted holoenzyme. Since no drastic change in the protein conformation was observed among the free SND100-, SND103-, SND106- and SND109-sigmaA factors, and that a more extended deletion at the N-terminus of sigmaA (up to 129 amino acid deletion) would increase the core-binding activity of mutant sigmaA factors, I propose that sigmaA factors with more than 103 amino acids being deleted at the N-terminus do not possess functional conformation when they are associated with core RNA polymerase.
35
Lakowski, Jörn. « Analysis of an evolutionarily conserved distant regulatory region downstream of the Pax6 gene ». 2003. http://purl.galileo.usg.edu/uga%5Fetd/lakowski%5Fjorn%5F200308%5Fms.
Texte intégral
36
Mao, Wei-Chun, et 毛瑋俊. « Structural and functional distinctions of the non-major conserved region in Aeromonas caviae D1 chitinase ». Thesis, 2003. http://ndltd.ncl.edu.tw/handle/13556904675155049098.
Texte intégralRésumé :
碩士國立海洋大學
食品科學系
91
N-acetylchitooligosaccharides have already been used in many fields and it’s also valuable. Our laboratory had made efforts in this field for several years. We had cloned high chitinolytic activity chitinase gene from Aeromonas caviae D1, and we had established the optimum condition of induction-expression and the production of N-acetylchitooligosaccharides. When we were proceeding the alignment of the amino acid sequence of A. caviae D1 ChiA, we found that it’s highly conserved with the putative active site of Alteromonas sp. O-7 ChiA, Serratia marcescens ChiA, ChiB and Bacillus circulans WL-12 ChiA1, ChiD. After we had proceeded the point mutation in the chitinase conserved region of A. caviae D1 ChiA, we found the significant decrease of N-acetylchitobiase and N-acetylchitotriase activity, but it’s not totally destructed. Therefore we presumed other regions besides the conserved one must have its contribution. In the study, we cloned the non-major conserved region chi300 and the chitin binding domain chBD in the A. caviae D1 ChiA. They were expressed in the E. coli BL21 (DE3) pLysS using the pET-20b(+) expression system. The His-Tag-affinity-purified recombinant Chi300 and ChBD had molecular mass about 38.4 and 15.5 kDa. When we were proceeding the activity analysis of Chi300 and ChBD, we found that they don’t have activity toward lower oligomerized substrates. The N-acetylchitobiase and N-acetylchitotriase activity of G561 are about 41.79% and 44.65% of ChiA, respectively. It showed the non-major conserved region Chi300 could contribute to the whole enzyme hydrolysis toward lower oligomerized substrates. When we added Chi300 and ChBD to the ChiA or G561, we didn’t find the significant effect of hydrolysis in lower oligomerized substrates. In the test of substrate binding specificity, neither Chi300 nor ChBD could have satisfying binding ability. We presumed during the protein folding, Chi300 and ChBD had already lost the normal conformation in ChiA. It could be caused by the amino residues besides the ChBD blocked the angle between two planes during the protein folding. So, it destroyed the binding ability.
37
Shaffer, Robert. « Role of a highly conserved region of the NF-kappaB essential modulator in its scaffolding function ». Thesis, 2018. https://hdl.handle.net/2144/34456.
Texte intégralRésumé :
Scaffold proteins facilitate many aspects of intracellular signaling. These proteins can regulate two or more proteins in the same pathway, or coordinate signaling from multiple pathways. Scaffold proteins are therefore key control points for the flux of signaling and play essential roles in biological systems. There are four possible mechanisms by which scaffold proteins achieve activation and propagate signaling: 1) rigid protein binding between two or more proteins to co-localize binding partners, 2) ligand-induced activation such as may result from a conformational change, 3) disorder-to-order transition where the scaffold protein folds as a result of a protein-protein interaction, and 4) dynamic processes such as phosphorylation. The scaffold protein NF-κB essential modulator (NEMO) functions via ligand-induced activation and serves as the key control point for canonical NF-κB signaling. The work described in this thesis investigates the role of a previously uncharacterized domain within NEMO that is required for function, which we term the Intervening Domain (IVD). Bioinformatic analysis reveals a high level of sequence conservation across species within this domain. Conformational changes following ligand binding are observed for NEMO and these changes require conserved sequences in the IVD. Additionally, a functional IVD is shown to increase the binding affinity of NEMO for IKKβ, enhance the thermal stability of NEMO, and is required to propagate NF-κB signaling in cells. A fluorescence-based assay is also developed to characterize the formation of a complex composed of NEMO, a zinc ion, and IκBα. A separate fluorescence-based assay is developed to measure IKK activity and is used to determine that NEMO alone or in the presence of linear tetraubiquitin does not enhance the rate of IKKβ phosphorylation of an IκBα-derived peptide. Furthermore, a number of organic small molecules and macrocycles are screened against the NEMO-IKKβ interaction. One small molecule was validated as an inhibitor and its biophysical properties and inhibition kinetics are described in this thesis. These analyses represent the first characterization of a highly conserved domain required for the function of the key control point in NF-κB signaling. The IVD domain of NEMO could be targeted for development of an allosteric effector for therapeutic discovery.
38
(9143657), Phillip S. Rushton. « Structure of the Plant-Conserved Region of Cellulose Synthase and Its Interactions with the Catalytic Core ». Thesis, 2020.
Trouver le texte intégralRésumé :
The processive plant cellulose synthase (CESA) synthesizes (1→4)-β-D-glucans. CESAs assemble into a six-fold symmetrical cellulose synthase complex (CSC), with an unknown symmetry and number of CESA isomers. The CSC synthesizes a cellulose microfibril as the fundamental scaffolding unit of the plant cell wall. CESAs are approximately 110 kDa glycosyltransferases with an N-terminal RING-type zinc finger domain (ZnF), seven transmembrane α-helices (TMHs) and a cytoplasmic catalytic domain (CatD). In the CatD, the uridine diphosphate glucose (UDP-Glc) substrate is synthesized into (1→4)-β-D-glucans. The ZnF is likely to facilitate dimers in the CSC. Recombinant class-specific region (CSR), a plant specific insertion to the C-terminal end of the CatD is also known to form dimers in vitro. The CSR sequence is the primary source of distinction between CESA isoforms and class structure. Also within the CESA CatD is a 125-amino acid insertion known as the plant-conserved region (P-CR), whose molecular structure was unknown. The function of the P-CR is still unclear, especially in the context of complete CESA and CSC structures. Thus, one major knowledge gap is understanding how multimeric CSCs synthesize multiple chains of (1→4)-β-D-glucans that coalesce to form microfibrils. The specific number of CESAs in a CSC and how interactions of individual CESA isoforms contribute to the CSC are not known. Elucidating the structure-function relationships of the P-CR domain, and with the consideration of the ability of CSR and ZnF domains to dimerize, it is possible to more completely model the structure of the CSC.
Recombinantly expressed rice (Oryza sativa) secondary cell wall OsCESA8 P-CR domain purifies as a monomer and shows distinct α-helical secondary structure by circular dichroism analysis. A molecular envelope of the P-CR was derived by small angle X-ray scattering (SAXS). The P-CR was crystallized and structure solved to 2.4 Å resolution revealing an anti-parallel coiled-coiled domain. Connecting the coiled-coil α-helices is an ordered loop that bends back towards the coiled-coils. The P-CR crystal structure fits the molecular envelope derived by SAXS, which in turn fits into the CatD molecular envelope. The best fit places the P-CR between the membrane and substrate entry portal. In depth analysis of structural similarity to other proteins, and 3D-surface structure of the P-CR, leads to hypotheses that it could function in protein-protein interactions as a dimer, trimer or tetramer in the CSC, that it could form protein-protein interactions with CESA-interacting proteins, and/or modulate substrate entry through its N- and/or C-terminus. From modeling, hypothetically important residues within the P-CR or related to the P-CR through potential protein contacts were mutated in Arabidopsis thaliana AtCESA1 constructs. These constructs were expressed in the temperature-sensitive radial swelling (rsw) rsw1-1 mutant of AtCESA1 to test for complementation of growth phenotypes at restrictive temperatures. Preliminary experiments indicate that some mutated CESA1 sequences fail to complement the rsw1-1 phenotype, suggesting that specific functions of individual amino can be tested using this system.
39
Jian, Ming Zhu, et 簡銘助. « Functional analysis of a small RNA generated from a highly conserved region of the Streptococcus parasanguinis FW213 chromosome ». Thesis, 2016. http://ndltd.ncl.edu.tw/handle/77ra2h.
Texte intégral
40
Mannam, Praveen. « Immune response and protection against Streptococcus pyogenes after vaccination with Lactococcus lactis that expresses conserved region of M6 protein ». Thesis, 2003. http://hdl.handle.net/1957/30816.
Texte intégralRésumé :
Most pathogens gain access to their host through mucosal surfaces. It is
therefore desirable to develop mucosal vaccines that elicit an immune response
to prevent this crucial first step in infection. Current mucosal vaccines are live
attenuated strains of pathogens. More recent efforts have focused on the use of
recombinant non-pathogenic gram-positive bacteria as live vaccine delivery
vectors. Here I have tested the potential of Lactococcus lactis to be used as a
vaccine vector. A recombinant strain of L. lactis has been constructed which
expresses and displays on its surface the C repeat region (CRR) of the M6
protein of Streptococcus pyogenes. I show that nasal vaccination of mice with
this strain elicited strong salivary IgA and serum lgG response. These responses
protected mice against a nasal challenge with S. pyogenes. Subcutaneous
vaccination with the same strain of L. lactis produced a strong serum lgG
response, but no salivary lgA response. Subcutaneous vaccination did not
protect the mice against nasal infections when the mice were challenged with
S. pyogenes. The immune response and protection afforded by concomitant
vaccination by both nasal and subcutaneous routes were better that that seen in
nasal vaccination alone. This study shows that an effective vaccine against
S. pyogenes is possible using L. lactis as a vaccine vector. It also opens up the
potential of L. lactis to be used in the development of vaccines to other mucosal
infections.Graduation date: 2004
41
Martínez-Lumbreras, S., E. M. Krysztofinska, A. Thapaliya, A. Spilotros, D. Matak-Vinkovic, E. Salvadori, P. Roboti et al. « Structural complexity of the co-chaperone SGTA : a conserved C-terminal region is implicated in dimerization and substrate quality control ». 2018. http://hdl.handle.net/10454/17888.
Texte intégralRésumé :
YesProtein quality control mechanisms are essential for cell health and involve delivery of proteins to specific cellular compartments for recycling or degradation. In particular, stray hydrophobic proteins are captured in the aqueous cytosol by a co-chaperone, the small glutamine-rich, tetratricopeptide repeat-containing protein alpha (SGTA), which facilitates the correct targeting of tail-anchored membrane proteins, as well as the sorting of membrane and secretory proteins that mislocalize to the cytosol and endoplasmic reticulum-associated degradation. Full-length SGTA has an unusual elongated dimeric structure that has, until now, evaded detailed structural analysis. The Cterminal region of SGTA plays a key role in binding a broad range of hydrophobic substrates, yet in contrast to the well-characterized N-terminal and TPR domains, there is a lack of structural information on the C-terminal domain. In this study, we present new insights into the conformation and organization of distinct domains of SGTA and show that the C-terminal domain possesses a conserved region essential for substrate processing in vivo. We show that the C-terminal domain region is characterized by α-helical propensity and an intrinsic ability to dimerize independently of the N-terminal domain. Based on the properties of different regions of SGTA that are revealed using cell biology, NMR, SAXS, Native MS, and EPR, we observe that its C-terminal domain can dimerize in the full-length protein and propose that this reflects a closed conformation of the substrate-binding domain. Our results provide novel insights into the structural complexity of SGTA and provide a new basis for mechanistic studies of substrate binding and release at the C-terminal region.
MRC New Investigator Research Grant: G0900936; BBSRC grants: BB/L006952/1 and BB/L006510/1; BBSRC grant: BB/N006267/1; Wellcome Trust Investigator Award in Science: 204957/Z/16/Z; BBSRC grant: BB/J014567/1
42
Thompson, Sunnie R. « Characterization of conserved sequences within the 3' untranslated region of messenger RNA that regulate translation through changes in poly (A) tail length ». 1998. http://catalog.hathitrust.org/api/volumes/oclc/40308502.html.
Texte intégral
43
chen, chun-chin, et 陳秋錦. « Functional analysis of the small RNA derived from the highly conserved 3’-untranslated region of Japanese encephalitis virus in infected mammalian cells ». Thesis, 2005. http://ndltd.ncl.edu.tw/handle/22361143479344785083.
Texte intégralRésumé :
碩士國立東華大學
生物技術研究所
93
英文摘要 Japanese encephalitis virus (JEV) contains a single positive-strand RNA genome of 10,976 nucleotides in length and is not formally thought to generate subgenomic RNA molecules during replication. Previous studies in our lab have reported the abundant accumulation of a 3’-terminal 521- to 523-nucleotide genome fragment, representing the highly conserved region of the 3’-untranslated region, in JEV-infected cells (Journal of Virology 78:5133, 2004). To address a possible function of the small RNA during viral replication, several approaches were carried out. Systematic quantification of plus- and minus-stand viral RNA synthesis using Northern hybridization, RNase protection, and RT-Real-time PCR assays suggested that the presence of the small RNA may play a role in the limitation of minus-stand RNA synthesis. Results from Northern analysis reveals that a minus-strand complement of the small RNA is not found, but rather only a minus-strand RNA that is 2X genome size is found. To elucidate a possible function of the small RNA and its complementary sequence during viral replication, unit-length (i.e., 523-nt) plus- and minus-strand forms of the small RNA were separately transfected in virus-infected cells and the effects on plusand minus-strand accumulation were measured. By strand-specific Northern hybridization and RT-real-time PCR assays. Transfection of the plus-sense small RNA appeared not to affect plus-strand viral RNA accumulation. However, transfection of the minus-sense small RNA caused a change in the migration pattern of the normally observed 2X minus-strand RNA in that nearly equal amounts of 1X-sized minus-strand 3 RNA are now found. The effect of transfection of the small plus-strand RNA on minus-strand accumulation remains to be determined. These results suggest that features of the minus-strand RNA may play a regulatory role during RNA synthesis in vivo.
44
Van, der Sluis Rencia. « Investigation and characterisation of the genetic variation in the coding region of the glycine N-acyltransferase gene / Rencia van der Sluis ». Thesis, 2015. http://hdl.handle.net/10394/15639.
Texte intégralRésumé :
Thorough investigation of the glycine conjugation pathway has been neglected over the last 30 years. Environmental factors, nutrition, and the chronic use of medications are increasing the exposure of humans to benzoate and drugs that are metabolized to acyl-CoA intermediates. Glycine conjugation of mitochondrial acyl-CoAs, catalysed by glycine N-acyltransferase (GLYAT, E.C. 2.3.1.13), is an important metabolic pathway responsible for maintaining adequate levels of free coenzyme A (CoASH). However, because of the small number of pharmaceutical drugs that are conjugated to glycine, the pathway has not yet been characterised in detail. Therefore, one of the objectives of this thesis was to develop a better understanding of glycine conjugation and its role in metabolism. In humans and animals a number of endogenous and xenobiotic organic acids are conjugated to glycine. Glycine conjugation has generally been assumed to be a detoxification mechanism, increasing the water solubility of organic acids in order to facilitate urinary excretion. However, recently it was proposed that the role of the amino acid conjugations, including glycine conjugation, is to regulate systemic levels of amino acids that are also utilised as neurotransmitters in the central nervous systems of animals. The glycine deportation hypothesis was based on the observation that, compared to glucuronidation, glycine conjugation does not significantly increase the water solubility of aromatic acids. A thorough review of the literature for this thesis showed that the major role of glycine conjugation, however, is to dispose of the end products of phenylpropionate metabolism. The review also introduced the new perspective that mitochondrial glycine conjugation prevents the accumulation of benzoate in the mitochondrial matrix by forming hippuric acid a less lipophilic conjugate that can be more readily transported out of the mitochondria. Although organic anion transporters can export benzoate from the matrix, this process would likely be futile because benzoic acid can simply diffuse back into the matrix. Hippurate, however, is significantly less lipophilic and therefore less capable of diffusing into the matrix. It is therefore not the transport out of the mitochondrial matrix that is facilitated by glycine conjugation, but rather the ability of the glycine conjugates to re-enter the matrix that is decreased. Lastly, glycine conjugation of benzoate also exacerbates the dietary deficiency of glycine in humans. Because the resulting shortage of glycine can negatively influence brain neurochemistry and the synthesis of collagen, nucleic acids, porphyrins, and other important metabolites, the risks of using benzoate as a preservative should not be underestimated.
To date, no defect of the glycine conjugation pathway has been reported and this, together with the fact that GLYAT plays an important role in hepatic metabolism, suggests that this pathway is essential for survival. GLYAT activity affects mitochondrial ATP production, glycine availability, CoASH availability and the toxicity of various organic acids. Therefore, variation in the glycine conjugation pathway could influence liver cancer, musculoskeletal development and mitochondrial energy metabolism. Significant interindividual variation exists in glycine conjugation capacity. The molecular basis for this variability is not known. The main aim of this thesis was to investigate and characterise the genetic variation in the coding region of the GLYAT gene. This was accomplished by firstly, investigating the influence of non-synonymous single nucleotide polymorphisms (SNPs) on the enzyme activity of a recombinant human GLYAT and secondly, by analysing the level of genetic
variation in the coding region of the GLYAT gene using existing worldwide population data. To investigate the influence of non-synonymous SNPs in the GLYAT gene on the enzyme activity, a recombinant human GLYAT was prepared, and characterised. Site-directed mutagenesis was used to generate six variants of the enzyme (K16N; S17T; R131H; N156S; F168L; R199C). The variants were expressed, purified, and enzymatically characterised. The enzyme activities of the K16N, S17T and R131H variants were similar to that of the wild-type, whereas the N156S variant was more active, the F168L variant less active, and the R199C variant was inactive. The results showed that SNP variations in the human GLYAT gene can influence the kinetic properties of the enzyme. The genetic variation data of the human GLYAT open reading frame (ORF) available on public databases was investigated by formulating the hypothesis that due to the essential nature of the glycine conjugation pathway, the genetic variation in the ORF of the GLYAT gene should be low and that deleterious alleles will be found at low frequencies. Data from the i) 1000 Genome Project, ii) the HapMap Project, and iii) the Khoi-San/Bantu Sequencing Project was downloaded from available databases. Sequence data of the coding region of a small cohort of South African Afrikaner Caucasian individuals was also generated and included in the analyses. In the GLYAT ORF of the 1537 individuals analysed, only two haplotypes (S156 and T17S156) out of 14 haplotypes were identified in all populations as having the highest haplotype frequencies (70% and 20% respectively). The S156C199 and S156H131 haplotypes, which have a deleterious effect on the enzyme activity of a recombinant human GLYAT, were detected at very low frequencies. The results of this study indicated that the GLYAT ORF is remarkably conserved, which supports the hypothesis that the glycine conjugation pathway is an essential detoxification pathway. The findings presented in this thesis highlight the importance that future investigations should determine the in vivo capacity of the glycine conjugation pathway for the detoxification of benzoate and other xenobiotics.PhD (Biochemistry), North-West University, Potchefstroom Campus, 2015
45
Khare, Tarang [Verfasser]. « Influence of assisted reproductive technologies on imprinting centers and functional characterization of conserved elements in Beckwith Wiedemann syndrome (BWS) region / by Tarang Khare ». 2007. http://d-nb.info/982693001/34.
Texte intégral
46
Chang, Yu-Chia, et 張毓嘉. « Study on the Importance of the Conserved Octamer 5’-GGAAGAGC-3’ Located in the Viral 3’ Untranslated Region for the Translation of Coronaviruses ». Thesis, 2019. http://ndltd.ncl.edu.tw/cgi-bin/gs32/gsweb.cgi/login?o=dnclcdr&s=id=%22107NCHU5628005%22.&searchmode=basic.
Texte intégralRésumé :
碩士國立中興大學
獸醫病理生物學研究所
107
The 3’ untranslated region (UTR) of betacoronavirus consists of four functional RNA secondary structures: bulged stem-loop (BSL), pseudoknot (PK), hypervariable region (HVR), and minimal region at 3’ terminus, and these structures have been demonstrated to be able to regulate coronavirus gene expression in cis. Within the hypervariable region (HVR), the sequence motif 5’-GGAAGAGC-3’, which is defined as octamer (oct), is almost universally conserved among coronaviruses, suggesting its potentially critical role in coronavirus biology; however, its function remains unknown. Previous study has shown that the oct is not essential for viral replication of murine hepatitis virus (MHV) in vitro; however, the HVR (including oct) deletion mutants affects MHV pathogenesis in infected mice. Since viral replication and pathogenicity are associated with viral proteins, it is possible that the oct may affect MHV pathogenicity through modulating viral translation. Therefore, we hypothesized that the conserved oct within the HVR plays a crucial role in coronavirus translation. For this aim, we constructed various oct or HVR mutants in both bovine coronavirus (BCoV) defective interfering (DI) RNA and MHV full-length genome to determine the effects of the mutations on translation in cells by Western blot and thus the function of oct on coronavirus translation. The results suggested that the oct has positive regulatory function for translation of the BCoV DI RNA, subgenomic RNA and the MHV full-length genome. The sequence specificity of oct and the HVR structure where oct is located are associated with coronavirus translation. In addition, other RNA elements located in the 3’ UTR, such as BSL and PK, may also be involved in the coronavirus translation. In this study, we for the first time demonstrate the important role of the universal octamer 5’-GGAAGAGC-3’ for coronavirus translation. In addition, we also provide the evidence that the other RNA elements in the viral 3’ UTR may participate in the translation mechanism of coronaviruses.
47
Uthaman, Yazhisai, et 葉意香. « Untranslatable tospoviral NSs fragment enhances the broad resistance conferred by L gene conserved region in transgenic plants with or without a selection marker gene ». Thesis, 2015. http://ndltd.ncl.edu.tw/handle/41454221085296715568.
Texte intégralRésumé :
博士國立中興大學
植物病理學系所
103
ABSTRACT Tospovirus, the only plant-infecting viruses in the family Bunyaviridae, cause serious damages on various economic crops all over the world. Watermelon silver mottle virus (WSMoV) and Melon yellow spot virus (MYSV), the two members of the genus Tospovirus, are the major limiting factors for cucurbits cultivation in Taiwan. In our earlier studies, transgenic tomato lines carrying the conserved region containing the RNA- dependent RNA polymerase (RdRp) motifs within the L gene of WSMoV confer broad-spectrum resistance against different tospoviruses mediated by post-transcriptioned gene silencing (PTGS). In this study, the enhanced broad resistance against distinct tospoviruses, in transgenic tobacco plants conferred by the conserved regions of L, N and NSs genes of tospoviruses were generated. Furthermore, marker-free transgenic tobacco plants carrying the L,N and NSs conserved regions of WSMoV and conferring broad resistance to distinct tospoviruses were produced . Our marker-free approach was further extended to produce marker-free economically important crops such as melon (Cucumis melo L.) carrying the conserved regions of L,N and NSs genes of WSMoV. Chapter 1, “Literature review and research objective” describes the background informations, references and research objectives of this this study. Chapter 2, “Untranslatable tospoviral NSs fragment coupled with L conserved region enhances transgenic resistance against the homologous virus and a serologically unrelated tospovirus”. In this study, Nicotiana benthamiana transgenic lines carrying individual untranslatable constructs comprised of the conserved region of the L gene (denoted as L), the 5′ half of NSs coding sequence (NSs) or the antisense fragment of whole N coding sequence (N) of Watermelon silver mottle virus (WSMoV), individually or in combination, were generated. A total of 15 -17 transgenic Nicotiana benthamiana lines carrying individual transgenes were evaluated against the WSMoV and the serologically unrelated Tomato spotted wilt virus (TSWV). Among lines carrying single or chimeric transgenes, the level of resistance ranged from susceptible to completely resistant against WSMoV. From the lines carrying individual transgenes and highly resistant to WSMoV (56-63% of lines assayed), 30% of the L lines (3/10 lines assayed) and 11% of NSs lines (1/9 lines assayed) were highly resistant against TSWV. The chimeric transgenes provided higher degrees of resistance against WSMoV (80-88%), and the NSs fragment showed an additive effect to enhance the resistance to TSWV. Particularly, the chimeric transgenes with the triple combination of fragments, namely L/NSs/N or HpL/NSs/N (a hairpin construct), provided a higher degree of resistance (both 50%, with 7/14 lines assayed ) against TSWV. Our results indicate that the untranslatable NSs fragment is able to enhance the transgenic resistance conferred by the L conserved region. The better performance of L/NSs/N and HpL/NSs/N in transgenic N. benthamiana lines suggests their potential usefulness in generating high levels of enhanced transgenic resistance against serologically unrelated tospoviruses in agronomic crops. Chapter 3, “Marker-free homozygous transgenic tobacco plants with resistance against tospoviruses of different serogroups and serotype”. In this study, to develop selectable marker-free transgenic plants resistant to different tospoviruses, we adopted a co-transformation system. Agrobacterium harboring pBI2T-based binary vectors, each with two T-DNAs separately carrying the selection marker gene (SMG) nptII and the construct with the aforementioned L fragment, alone or in combination with the NSs and N fragments , were used for transformation of Nicotiana benthamiana plants. Transgenic lines (12-18 for each construct) with high degrees of resistance against two serologically unrelated tospoviruses, Watermelon silver mottle virus (WSMoV) and Tomato spotted wilt virus (TSWV), were obtained. R1 progenies of 7 self-pollinated highly resistant transgenic R0 lines were further analyzed for the segregation of the SMG and the viral construct by PCR. When the individuals of the R3 progeny of the marker-free R2 homozygous transgenic plant were challenged with members of different tospoviruses of WSMoV, TSWV and Impatiens necrotic spot virus ( INSV ), resistance levels of 90-100% were noticed, indicating that the marker-free R2 and R3 homozygous transgenic N. benthamiana plants confer high degrees of broad resistance against tospoviruses of different serogroups and serotype. This approach is currently being extended to commercially important crops such as tomato, watermelon and melon. Supplementary information, “Generation of transgenic melon plants with marker-free hairpin construct” . In this study, using the co-transformation method, Agrobacterium harboring pBI2T 1.5 binary vector with two T-DNAs carrying the nptII selection marker gene and the gene of interest HpL/NSs/N (constructed using conserved regions of tospoviral L (replicase), N (nucleocapsid) and NSs (gene silencing suppressor) genes of tospoviruses) was used for transformation of melon (cv.Silver light) plant. The regenerated marker-free transgenic 12 melon plant lines showed the presence of transgene and marker gene when checked through PCR. The marker-free transgenic melon plant lines will be challenged with different tospoviruses such as WSMoV and MYSV.
48
Peng, Jui-Chu, et 彭瑞菊. « Occurrence of thrips-borne viruses infecting cucurbits in Taiwan and generation of broad-spectrum resistance in transgenic plants conferred by the conserved region of L genes of tospoviruses ». Thesis, 2011. http://ndltd.ncl.edu.tw/handle/59418743980813354305.
Texte intégralRésumé :
博士國立中興大學
植物病理學系所
99
Thrips-borne tospoviruses, belonging to the only plant-infecting genus Tospovirus in the family Bunyaviridae that cause severe damages in economic crops worldwide, are globally important. Watermelon silver mottle virus (WSMoV) and Melon yellow spot virus (MYSV), the members of the genus Tospovirus, are of the major threats for the cultivation of cucurbits in Taiwan. Melon (Cucumis melo L.) and watermelon (Citrullus lanatus Thunb.) are economically important crops in Taiwan. In this study, the occurrence of thrips-borne viruses infecting melon in Taiwan was investigated, and the broad-spectrum resistance in transgenic plants conferred by the conserved region of L genes of tospoviruses was generated. This dissertation is divided into four chapters as described below. Chapter 1, “ Literature review and research objectives” describes references relevant to this study and the objectives for the investigations. Chapter 2, “Occurrence of thrips-borne viruses infecting melon and watermelon in Taiwan” describing the incidence of virus infection in melon fields, a field survey was conducted from July 2007 to December 2009. The symptomatic tissues were collected from the principal cultivated areas in central and southern Taiwan. The anti-N protein-monoclonal antibodies (MAbs) and the N gene-specific primer pairs can be used to identify WSMoV and MYSV. The uncertain ELISA results for tospoviruses were further verified by reverse transcription-polymerase chain reaction (RT-PCR) using N gene-specific primer pairs for WSMoV and MYSV. Among 10,480 melon samples tested, 631 (6%) and 1,906 (18.2%) were found infected with WSMoV and MYSV, respectively, and only 17 mixed infections by both WSMoV and MYSV. Our results indicated that MYSV is the major tospovirus to invade melon in Taiwan. On the other hand, among 1,811 watermelon samples assayed, 22.4% and 9.2% samples were singly infected with WSMoV and MYSV, respectively, and 4 samples were infected with both viruses. Our results indicated that mixed infection with the two thrips-borne viruses is rare. Moreover, host preference for both viruses is different; WSMoV prevails on watermelon whereas MYSV is more widespread on melon. We conclude that MYSV has become a serious threat for watermelon and melon production in Taiwan and the possible control measures are discussed. Chapter 3, “Generation of broad-spectrum resistance in transgenic plants conferred by the conserved region of L genes of tospoviruses ”. In this investigation, the conserved region containing the RNA-dependent RNA polymerase (RdRp) motifs within the L gene of WSMoV, an important cucurbit-infecting tospovirus in Taiwan, was used as a transgene for transformation of Nicotiana benthamiana and Solanum esculentum mediated by Agrobacterium tumefaciens to generate broad-spectrum resistance to tospoviruses. Five different modified transgene constructs of the L gene conserved region, including WLm in a sense translatable orientation, WLmt and WLmts in non-translatable, WLmAs in antisense and WLmds in double-stranded inverted repeat, were used to evaluate broad-spectrum resistance in transgenic plants. A total of 46.7-70.0% transgenic N. benthamiana lines derived from these five transgenes showed resistance to WSMoV, and 35.7-100% of the WSMoV-resistant lines exhibited broad-spectrum resistance against four other serologically unrelated tospoviruses, including Tomato spotted wilt virus (TSWV), Groundnut ringspot virus (GRSV), Impatiens necrotic spot virus (INSV) and Peanut chlorotic fan-spot virus (PCFV). Northern analyses indicated that the broad-spectrum resistance is mediated by post transcriptional gene silencing (PTGS). To validate the L conserved region resistance in vegetable crops, we have transferred all the transgenes constructs in transgenic tomato plants and the results indicated that this L conserved region generate high levels of resistance against WSMoV and other distinct tospoviruses. This is the first report that using a single nucleotide fragment corresponding to the L gene conserved region as a novel transgenic approach to trigger broad-spectrum resistance for controlling different tospoviruses at the genus level. Chapter 4, “Broad-spectrum resistance to tospoviruses conferred by the marker-free transgene constructs containing the L gene conserved region of Watermelon silver mottle virus in tomato and melon”. Using the co-transformation method, the conserved region containing the RdRp motifs within L gene of WSMoV was constructed in a two T-DNAs binary vector and used to generate marker-free transgenic plants. Two constructs- MF-WLmAs and MF-3WLmds were evaluated for the broad-spectrum resistance. Our results preliminary indicated that the L gene conserved region is successfully used to generate marker-free transgenic tomato and melon lines conferring broad-spectrum resistance against different tospoviruses. The segregation and elimination of the selection marker nptII will be selected from the progenies after selfing.
49
OLIVEIRA, NOGUEIRA MARCELA CRISTINA. « Characterization of heterogeneous viral proteins by NMR methods : Human Adenovirus E1A and Human papillomavirus E7 proteins ». Doctoral thesis, 2016. http://hdl.handle.net/2158/1074811.
Texte intégralRésumé :
HPV-16 E7 and HAdV-E1A proteins have been studied for years and despite documented attempts the characterization of these proteins either through NMR or X-ray crystallography failed due to their heterogeneous structural and dynamic properties.
Thanks to the recently developed NMR approach to characterize highly heterogeneous proteins, in combination with clever sample preparation strategies, it was possible to complete the high resolution characterization through NMR of both, HPV16-E7 as well as HAdV-E1A. The information obtained, can now be used by the scientific community to answer the many open questions on the molecular determinants of the function of these two distinct proteins that are able to hijack cell regulation by a closely related mechanism. Indeed, the example of the high resolution study of one of the key post-translational modifications linked to the oncogenic process reported here just represents the first example of many studies that now can be performed taking advantage of the available NMR chemical shift assignment. This information can in turn be used to design innovative drugs that target, instead of well-structured proteins, these two IDPs.
50
Cheng, Yu-Ting, et 鄭宇婷. « The effect of mutation of the non-conserved cysteine residue in the C-terminal region of the triple-gene-block protein 2 on the infectivity of Bamboo mosaic virus ». Thesis, 2012. http://ndltd.ncl.edu.tw/handle/42283062301698130740.
Texte intégralRésumé :
碩士國立中興大學
生物化學研究所
100
The TGBp1, TGBp2 and TGBp3 encoded by the triple gene block (TGB) of Bamboo mosaic virus (BaMV) are required for virus movement across the cells.. The TGBp2 is transmembrane protein which has two conserved Cys residues (Cys-109 and Cys112) at their C-terminal tails. Previous study showed that the Cys-to-Ala substitutions of these two conserved residues in TGBp2 make the cell-to-cell movement of BaMV relatively inefficient and the systemic movement of BaMV severely inhibited. However, there is also a non-conserved Cys residue (Cys-119) at the C-terminal tail of TGBp2. To investigate whether Cys-119 of TGBp2 has similar importance to virus movement as the conserved ones, four mutant BaMVs which have Cys-to-Ala substitutions at position 119 of TGBp2 were constructed. and inoculated onto the leaves of Chenopodium quinoa and Nicotiana benthamiana. However, no disease symptom and GFP fluorescence were observed in the inoculated leave. To understand the reason causing the phenomenon, the amino sequence in the junction of TGBp2 and TGBp3 was analyzed. The result indicated that replacement of Cys-119 the final codon of TGBp2, with Ala will change the initiation codon, Met, of TGBp3 into Ser and thus affects the translation or the movement function of TGBp3. To overcome this problem, the Cys-119 of TGBp2 was replaced with Trp, which maintains the Met initiation codon of TGBp3. The infectivities of the four mutant BaMVs containing Cys-119-Trp were all lower than that of the wild-type. In addition, the TGBp2 in the membrane fraction of both the wild-type and mutant BaMV-infected N. benthamiana was analyzed by Western blot. Dimeric form of TGBp2, albeit with a much lower level, was detected in the tissues infected with the BaMV containing triple Cys substitutions in TGBp2. These results suggest that the conserved or non-conserved Cys residues are not essential for the formation of TGBp2 homo-multimer and it is the hydrophobic α-helical region which is responsible for the formation of TGBp2 multimer.