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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
31

Filogenia, biogeografia e evolução de estruturas secretoras de representantes da subtribo Cajaninae (Leguminosae, Papilionoideae, Phaseoleae)

Araujo, Wanderleia de Vargas January 2019 (has links)
Orientador: Silvia Rodrigues Machado / Resumo: Leguminosae é a terceira maior família dentre as Angiospermas, é cosmopolita, podendo ocorrer em florestas tropicais úmidas, florestas secas, savanas, regiões mediterrâneas e desérticas. Papilionoideae, subfamília com maior riqueza de espécies de Leguminosae, apresenta Phaseoleae como uma de suas tribos de maior importância econômica e alto número de espécies. Cajaninae, por sua vez, é a maior subtribo de Phaseoleae, destacando-se por apresentar aproximadamente 490 espécies distribuídas em 10 gêneros. Os representantes desta subtribo possuem distribuição pantropical, com apenas Rhynchosia e Eriosema ocorrendo nos neotrópicos. De modo geral, as espécies desta subtribo ocorrem em campos graminosos, florestas tropicais secas, regiões semiáridas, áreas degradadas e ambientes propensos à passagem do fogo. A ocorrência das espécies de Cajaninae nestes diferentes ambientes pode estar relacionada à presença de estruturas secretoras, como glândulas vesiculares e tricomas de base bulbosa. Apesar do conhecimento sobre a existência destas estruturas peculiares neste grupo desde o século 19, nenhum estudo detalhado de anatomia, ultraestrutura ou estudos com enfoque evolutivo haviam sido realizados. A subtribo tem sido considerada monofilética, porém os poucos trabalhos filogenéticos existentes abordam Phaseoleae como um todo, possuindo uma amostragem muito baixa dos representantes de Cajaninae, o que não esclarece sua monofilia. Considerando o pouco conhecimento sobre as relações filogené... (Resumo completo, clicar acesso eletrônico abaixo) / Abstract: Leguminosae is the third largest family among Angiosperms, is cosmopolitan, occurring in humid tropical forests, dry forests, savannas, Mediterranean and desert regions. Papilionoideae, a subfamily with the highest species richness of Leguminosae, presents Phaseoleae as one of its tribes of major economic importance and high number of species. Cajaninae, in turn, is the largest subtribe of Phaseoleae, standing out to present approximately 490 species distributed in 10 genera. The representatives of this subtribe have pantropical distribution, with only Rhynchosia and Eriosema occurring in the neotropics. The species of this subtribe occur in greenfields, dry tropical forests, semi-arid regions, degraded areas and environments prone to fire. The occurrence of Cajaninae species in these different environments may be related to the presence of secretory structures, such as vesicular glands and bulbous based-trichomes. Despite the knowledge about the existence of these peculiar structures in this group since the 19th century, no detailed study of anatomy, ultrastructure or evolutionary approach studies had been performed. The subtribe has been considered monophyletic, but the few existing phylogenetic works address Phaseoleae as a whole, having a very low sampling of Cajaninae representatives, which does not clarify its monophyly. Considering the little knowledge about the phylogenetic relationships in Cajaninae, on the secretory structures that are peculiar to this group and the... (Complete abstract click electronic access below) / Doutor
32

Gene expression profiling in different stages of development of Arabidopsis thaliana leaftrichomes at the single cell level

Kryvych, Sergiy January 2007 (has links)
Each organ of a multicellular organism is unique at the level of its tissues and cells. Furthermore, responses to environmental stimuli or developmental signals occur differentially at the single cell or tissue level. This underlines the necessity of precise investigation of the “building block of life” -the individual cell. Although recently large amount of data concerning different aspects of single cell performance was accumulated, our knowledge about development and differentiation of individual cell within specialized tissue are still far from being complete. To get more insight into processes that occur in certain individual cell during its development and differentiation changes in gene expression during life cycle of A. thaliana leaf hair cell (trichome) were explored in this work. After onset of trichome development this cell changes its cell cycle: it starts endoreduplication (a modified cell cycle in which DNA replication continues in the absence of mitosis and cytokinesis). This makes trichomes a suitable model for studying cell cycle regulation, regulation of cell development and differentiation. Cells of interest were sampled by puncturing them with glass microcapillaries. Each sample contained as few as ten single cells. At first time trichomes in initial stage of trichome development were investigated. To allow their sampling they were specifically labelled by green fluorescent protein (GFP). In total three cell types were explored: pavement cells, trichome initials and mature trichomes. Comparison of gene expression profiles of these cells allowed identification of the genes differentially expressed in subsequent stages of trichome development. Bioinformatic analysis of genes preferentially expressed in trichome initials showed their involvement in hormonal, metal, sulphur response and cell-cycle regulation. Expression pattern of three selected candidate genes, involved in hormonal response and early developmental processes was confirmed by independent method. Effects of mutations in these genes on both trichome and plant development as well as on plant metabolism were analysed. As an outcome of this work novel components in the sophisticated machinery of trichome development and cell cycle progression were identified. These factors could integrate hormone stimuli and network interactions between characterized and as yet unknown members of this machinery. I expect findings presented in this work to enhance and complement our current knowledge about cell cycle progression and trichome development, as well as about performance of the individual cell in general. / Jedes Organ eines vielzelligen Organismus weißt einzigartige Merkmale auf seiner Gewebe und Zellebene auf. Darüber hinaus, werden entwicklungsabhängige sowie aus der Umwelt empfangene Signale zelltypspezifisch interpretiert. Aus dieser Spezialisierung einzelner Zellen ergibt sich somit unmittelbar die Notwendigkeit einzelne Zellen, als Bausteine komplexer Organe, individuell zu untersuchen. Obwohl in den letzten Jahrzehnten große Datenmengen über verschiedene Aspekte einzelner Zellen akkumuliert wurden, ist das Gesamtbild der Differenzierung und Entwicklung individueller Zellen in einem vielzelligen Organismus weitgehend unbekannt. Um der Frage nachzugehen, welche Prozesse sich in einer einzelnen Zelle während ihrer Differenzierung und Entwicklung abspielen, wurden Genexpressionsprofile einzelner Blatthaarzellen der Pflanze Arabidopsis thaliana in verschiedene Entwicklungsstadien erstellt. Nach dem Beginn der Entwicklung einer Protodermalzelle in ein Blatthaar (Trichom) kommt es zu einem Umschalten des Zellzyklus; Endoreduplikation setzt ein. Dies bedeutet, dass DNA repliziert wird, aber keine Zellteilung mehr stattfindet. Aus diesem Grunde eignen sich heranwachsende Trichome besonders gut Mechanismen zu erforschen, die in Verbindung mit der Zellzyklusregulation und Zellentwicklung stehen. Die Inhalte ausgewählter Einzelzellen wurden mit Glasmikrokapillaren extrahiert. Jeweils zehn derartige Einzelzellextrakte wurden daraufhin vereint. Als besonders hervorzuheben gilt, dass es uns in dieser Studie zum ersten mal überhaupt gelang die Inhalte einzelner Trichomzellen in ganz frühen Entwicklungsstadien zu extrahieren und anschließend zu analysieren. Um die Extraktion der Inhalte dieser frühen Zellstadien überhaupt zu ermöglichen, war es erforderlich diese mit dem grün fluoreszierenden Protein (GFP) zu markieren. Neben den Trichominitialzellen wurden ausgewachsene Trichomzellen sowie Epidermiszellen (Pavementzellen) mittels der Einzelzelltechnik untersucht. Ein Vergleich der erstellten Genexpressionsprofile dieser drei Zelltypen ermöglichte es Gene zu identifizieren, die in den ausgewählten Entwicklungsstadien der Trichombildung differentiell induziert wurden. Mittels bioinformatischer Analysemethoden gelang es, Gruppen von Genen zu identifieren, die exklusiv in Trichominitialzellen exprimiert sind und den Kategorien, Hormonregulation, Metallhomeostase, Schwefelstoffwechesol sowie Zellzyklusregulation zuzuordnen sind. Weiterhin wurde das Expressionsmuster dreier ausgewählter Kandidatengene mit alternativen Techniken verifiziert. Die ausgewählten Kandidatengene gehörten den Katergorien, Hormonrespons sowie frühe Entwicklungsprozesse, an. Darüber hinaus wurden Mutanten in allen drei Gene erzeugt und der Einfluss dieser Mutationen auf die Trichomentwicklung analysiert. Ein weiterer Aspekt der Mutantenanalyse lag in der Erstellung von Metabolitenprofilen ausgewählter Mutanten. Als ein wesentliches Ziel dieser Arbeit gelang es mir bisher unbekannte Komponenten in der Trichomentwicklung und damit der Zellzyklusregulation zu identifizieren. Diese neu identifizierten Komponenten führen zu einer Integration der hormonellen Kontrolle der Zellteilung und Entwicklung mit bisher unbekannten Faktoren. Ich erwarte, dass die von mir erbrachten Ergebnisse zu einem tieferen Verständnis der Prozesse, die an der Trichomentwicklung sowie an der Zellzyklusregulation beteiligt sind, beitragen. Insbesondere, zu einem erweiterten Verständnis des Verhaltens individueller Zellen in einem vielzelligen Organismus.
33

Analyse fonctionnelle du promoteur de la cembranetriène- diol-synthase spécifique des trichomes de Nicotiana sylvestris

Ennajdaoui, Hanane 25 September 2009 (has links) (PDF)
Chez le tabac, les trichomes glandulaires sécréteurs (TGSs) sont des structures pluricellulaires où s'effectuent la synthèse et la sécrétion de nombreux composés volatiles. Cette production spécifique dans les TGSs est la conséquence de la spécificité de l'expression transcriptionnelle des gènes des Terpènes synthases. Les promoteurs de ces gènes sont intéressants parce qu'ils peuvent être utilisés en bioingénieurie pour produire des biomolécules à forte valeur ajoutées (taxol, l'artémisinine) dans TGSs. L'un d'eux, le promoteur de la Cembratriène-diol-synthase (P1.1NsTPSO2a), actif dans les cellules de têtes des TGSs, a été isolé et transfecté dans N.sylvestris. L'analyse par délétions de P1.1NsTPSO2a a montré que deux fragments, 4c (100pb) et 400c (360 pb) sont importants pour l'expression spécifique dans les têtes de trichomes. La région 4c a été placée en amont du promoteur 35S minimum (-46) et du gène rapporteur GUS. Nous avons démontré que 4c est nécessaire et suffisant pour une expression dans les têtes de TGSs. Le fragment 400c pourrait jouer un rôle dans la répression du P1.1NsTPSO2a dans les cellules épidermiques et dans certaines parties des racines. Enfin, nous avons isolé par crible simple-hybride dans la levure un facteur de transcription putatif du trichome (NsZnF) pouvant reconnaître le fragment 400c. NsZnf appartient à la famille des facteurs de transcription GATA-ZincFinger III. Cette protéine possède un doigt de zinc, un domaine CCT et un domaine TIFY. L'expression transitoire dans N.benthamiana montre une localisation nucléaire de NsZnf compatible avec son rôle de facteur de transcription.
34

Morfologia das cipselas de Disynaphiinae e Praxelinae (Eupatorieae - Asteraceae)

Silva, Taynara Dayane Guimarães 26 February 2016 (has links)
Coordenação de Aperfeiçoamento de Pessoal de Nível Superior / Asteraceae (=Compositae) is one of the largest families of plants, comprises about 1,600 genera and 23,000 species. The family has a wide distribution in Brazil occurring in different vegetation formations. The Disynaphiinae and Praxelinae subtribes belong to Eupatorieae tribe, which currently has 19 subtribes. The cypselae and its accessory parts (pappus and carpopodium) have great taxonomic value and can be used as diagnostic to differentiate or group species and even genera. The boundaries between some genera are not well defined based on morphological usual features. The study of the morphology of cypselae in Disynaphiinae and Praxelinae will contribute to the characterization and can understanding their infrageneric relations. The aim is to describe the structure of the pericarp of the mature fruit of the representatives of Disynaphiinae and Praxelinae as well as the varieties of Chromolaena squalida, seeking common morphological characteristics distinct to these groups. Thereunto, we used a scanning electron microscopy and light microscopy. The trichomes, pericarp structure, and accessory parts of cypselae proved useful in taxonomic groups revealing a close relationship between species of each of the subtribes. These features were also important to exclude species e. g. Disynaphia praeficta. Our study also supports the varieties of Chromolaena squalida, allowing the correct identification. The phytomelanin was present in all cypselae studied, but their arrangement differs among the subtribes. The correlation between the number of bundles and ribs is not fixed in Praxelinae and ribs were not always associated with vascular bundles. / Asteraceae (= Compositae) é uma das maiores famílias de plantas, compreende cerca de 1.600 gêneros e 23.000 espécies. A família apresenta no Brasil uma ampla distribuição em diferentes formações vegetacionais. As subtribos Disynaphiinae e Praxelinae pertencem à tribo Eupatorieae, que atualmente apresenta 19 subtribos. As cipselas e suas partes acessórias (pápus e carpopódio) possuem grande valor taxonômico e podem ser usados como diagnósticos para diferenciar ou agrupar espécies e até gêneros. Os limites entre alguns gêneros não são bem definidos baseado nas características morfológicas tradicionais.O estudo da morfologia das cipselas em Disynaphiinae e Praxelinae contribuirá para a caracterização e o entendimento das relações infragenéricas nestas subtribos. O objetivou-se, com esta dissertação, descrever a micromorfologia e a estrutura do pericarpo do fruto maduro dos representantes de Disynaphiinae e Praxelinae, bem como das variedades de Chromolaena squalida, buscando características morfológicas comuns e distintas a estes grupos. Para isso, utilizou-se a Microscopia Eletrônica de Varredura e a Microscopia de luz. Nas subtribos Disynaphiinae e Praxelinae, características analisadas como o indumento, a estrutura do pericarpo e partes acessórias das cipselas, mostraram-se úteis na taxonomia dos grupos, revelando a proximidade entre as espécies de cada uma das subtribos, tais características também foram importantes na rejeição de espécies (Disynaphia praeficta). O presente estudo suporta as variedades de Chromolaena squalida, permitindo a correta identificação. A fitomelanina esteve presente em todas as cipselas, porém o arranjo dessa camada difere nas subtribos estudadas. A correlação entre o número de feixes vasculares e a presença de costelas não é fixa em Praxelinae e as costelas não necessariamente estavam associadas com feixes vasculares. / Mestre em Biologia Vegetal
35

Morfologia, funcionamento e influência de fatores exógenos no sistema secretor de óleo em espécies vegetais com ênfase no papel do citoesqueleto no processo de secreção

Tozin, Luiz Ricardo dos Santos. January 2018 (has links)
Orientador: Tatiane Maria Rodrigues / Resumo: A morfologia, histoquímica e ultraestrutura dos tricomas glandulares têm sido estudadas em muitas espécies vegetais. Entretanto, alguns aspectos têm sido pouco abordados, como o envolvimento do citoesqueleto na morfologia e funcionamento glandular. Estudo recente demonstrou a relação entre a predominância de filamentos de actina e microtúbulos em células secretoras e a composição da secreção em tricomas glandulares. Além disso, pesquisas têm comprovado o envolvimento dos elementos do citoesqueleto na origem e manutenção dos tricomas tectores em plantas, sem informações para os tricomas glandulares. Sabe-se que o funcionamento do citoesqueleto está relacionado com a disponibilidade do cálcio, sendo que baixas concentrações desse íon podem prejudicar processos modulados por microtúbulos e actina. Apesar da presença de tricomas glandulares representar um caráter constitutivo em diversas espécies vegetais, fatores exógenos podem influenciar o desenvolvimento e o funcionamento glandular. Estudos têm mostrado que o ataque de herbívoros induz a formação de tricomas glandulares, levando a produção de substâncias com potencial repelente ou inseticida. Os objetivos desse trabalho foram investigar o papel do citoesqueleto na morfogênese e funcionamento de tricomas glandulares e no transporte lipídico em células secretoras de óleo, além de investigar a influência da herbivoria no desenvolvimento e funcionamento de tricomas glandulares. Foram estudadas duas espécies de Lamiaceae (Hyptis v... (Resumo completo, clicar acesso eletrônico abaixo) / Abstract: The morphology, histochemistry and ultrastructure of glandular trichomes have been studied in many plant species. However, some aspects have been poorly approached, such as the involvement of the cytoskeleton on the gland morphology and functioning. Recent study demonstrated a relation between the predominance of actin filaments and microtubules in secretory cells and the secretion composition in glandular trichomes. In addition, researches have proven the involvement of the cytoskeletal elements in the origin and maintenance of non-glandular trichomes in plants, with no information for glandular trichomes. It is known that the cytoskeleton functioning is related with calcium availability and that low concentration of this ion can harm process modulated by actin filaments and microtubules. Despite the presence of glandular trichomes is a constitutive character in several plant species, exogenous factors can influence their development and functioning. Studies have showed that herbivore attacks induce the glandular trichomes formation, leading to the production of substances with repellent and insecticide potential. This work aimed to investigate the role of cytoskeleton in the glandular trichome morphogenesis and functioning, and in the lipid transport in oil secretory cells, in addition to investigate the influence of herbivory in the glandular trichomes formation and functioning. We studied two Lamiaceae species (Hyptis villosa and Ocimum gratissimum) and the model species ... (Complete abstract click electronic access below) / Doutor
36

Aspectos da biologia, caracterização foliar e manejo químico de Conyza bonariensis (L.) Cronquist (Asteraceae) e Conyza canadensis (L.) Cronquist (Asteraceae) / Aspects of the biology, leaf characteristics and chemical management of Conyza bonariensis (L.) Cronquist (Asteraceae) and

Inacio, Estela Maris 16 January 2012 (has links)
Made available in DSpace on 2016-06-02T18:55:21Z (GMT). No. of bitstreams: 1 4057.pdf: 2122562 bytes, checksum: c5fde2aa056e5c4a8b5e9d536009b775 (MD5) Previous issue date: 2012-01-16 / Financiadora de Estudos e Projetos / The genus Conyza includes approximately 60 species, which are distributed throughout most of the world. Globally the weed species Conyza canadensis and Conyza bonariensis infest more than 40 types of crops. Both species are noted for their ability to infest abandoned areas (vacant lots and roadsides), pastures, perennial crops (citrus and coffee) and annual crops (cotton, corn, soybeans and wheat). Knowledge of the biology of these weeds is required to inform management actions to control their spread for example to identify which is the best control strategy and time for action. We conducted experiments at the Center for Agricultural Sciences / UFSCar, between 2010 and 2011, to achieve 3 research objectives: (1) determine the germination behavior of C. canadensis and C. bonariensis under different environmental conditions [different temperatures (10oC, 15oC, 20oC, 25oC, 30oC and 35oC), light (with and without), sowing depth (0, 0.5, 1, 2, 3, 5, 7, and 10 cm) and germination in soils with different textures (sand, intermediate and clay)], (2) characterize the different types of leaf surface of C. bonariensis and C. canadensis by scanning electron microscopy, (3) determine the effects of the application of the herbicide glyphosate (0.42 kg a.i. ha-1), when mixed with ammonium glyphosate (0.5 kg a.i. ha-1), bentazon (0.72 kg a.i. ha-1), chlorimuron-ethyl (0.15 kg a.i. ha-1), carfentrazone-ethyl (0.03 kg a.i. ha-1), 2,4-D (1.0 L a.i. ha-1), metribuzin (0.48 kg a.i. ha-1) and sulfentrazone (0.6 kg ha-1), in addition to these herbicides applied in isolation. For both C. bonariensis and C. canadensis, the best seed germination and germination rate temperature was approximately 250C. Seed germination rate of both species was higher when exposed to light, compared with seeds germinated in the dark. Sowing depth and soil texture also influenced germination, with seeds of both species showing higher emergence rates in intermediate texture soils when they were sown on the soil surface (0 cm), whereas emergence rates declined at sowing depths ≥0.5 cm. Analysis of leaf surfaces revealed that both species are amphistomatic with stomata on the adaxial and abaxial leaf surfaces, that the non-glandular trichomes are unicellular and multicellular, and that C. bonariensis has a visually larger amount of trichomes on the adaxial surface. The most effective herbicide treatments for the chemical control of C. bonariensis were glyphosate + ammonium glyphosate, glyphosate + bentazon, glyphosate + chlorimuron - ethyl and glyphosate + metribuzin, whereas for C. canadensis, the best treatments were mixtures of glyphosate + ammonium glyphosate, glyphosate + bentazon and glyphosate + metribuzin. / O gênero Conyza inclui aproximadamente 60 espécies, as quais se distribuem em quase todo o mundo. As espécies Conyza canadensis e Conyza bonariensis, destacam-se por infestarem áreas abandonadas (terrenos baldios e margens de estradas), pastagens, culturas perenes (citros e café) e lavouras anuais (algodão, milho, soja e trigo). Em termos mundiais, estas espécies daninhas infestam mais de 40 culturas. É importante, quando se pensa em manejo das plantas daninhas, conhecer a biologia das plantas alvos, para assim detectar qual é o melhor controle e momento de ação. O experimento foi realizado no Centro de Ciências Agrárias/UFSCar, entre os anos de 2010 e 2011. Os objetivos desta pesquisa foram: (1) determinar o comportamento germinativo de C. canadensis e C. bonariensis em diferentes condições de temperatura (10oC, 15oC, 20oC, 25oC, 30oC e 35oC), luz (presença e ausência), profundidade de semeadura (0, 0.5, 1, 2, 3, 5, 7, e 10 cm) e germinação em solos com diferentes texturas (arenosa, média e argilosa); (2) caracterizar a superfície foliar das diferentes espécies de C. bonariensis e C. canadensis através da microscopia eletrônica de varredura; (3) determinar o tipo de interação do herbicida glyphosate (0,42 kg i.a ha-1), quando em mistura com amônio glufosinato (0,5 kg i.a ha-1), bentazon (0,72 kg i.a ha-1), chlorimuron - ethyl (0,15 kg i.a ha-1), carfentrazone - ethyl (0,03 kg i.a ha-1), 2,4-D (1,0 L i.a ha-1 ), metribuzin (0,48 kg i.a ha-1) e sulfentrazone (0,6 kg i.a ha-1), além dos mesmos herbicidas aplicados isoladamente. Para C. bonariensis e C. canadensis, a melhor temperatura para a germinação das sementes e índice de velocidade de germinação foi de aproximadamente 250C; ambas as espécies obtiveram maior taxa de germinação quando submetidas à luz comparadas com o tratamento de escuro absoluto, em relação à profundidade de semeadura nos diferentes solos, as sementes de ambas as espécies obtiveram maior taxa de emergência em solo de textura média quando estavam na superfície do solo (0 cm) a partir de 0,5 cm ocorreu redução da emergência das plântulas. Ambas as espécies são anfiestomáticas, apresentam estômatos na superfície adaxial e abaxial, possuem tricomas tectores unicelulares e pluricelulares, sendo que a espécie C. bonariensis possui visualmente maior quantidade de tricomas na face adaxial. Em relação ao manejo químico os tratamentos utilizando glyphosate + amônio - glufosinato, glyphosate + bentazon, glyphosate + chlorimuron - ethyl e glyphosate + metribuzin foram mais efetivos no controle de C. bonariensis; para C. canadensis, os melhores tratamentos foram às misturas de glyphosate + amônio - glufosinato, glyphosate + bentazon e glyphosate + metribuzin.
37

Úloha vybraných podjednotek komplexu exocyst ve vývoji epidermis Arabidopsis. / Subunits of exocyst complex in the development of Arabidopsis epidermis

Vojtíková, Zdeňka January 2013 (has links)
Exocyst is protein complex evolutionary conserved in yeasts, animals and plants, which plays a role in control of cell morphogenesis and polarity. It is a tethering complex whose function is to attach secretory vesicles to specifi c foci on plasma membrane. Complex exocyst is formed by eight subunits. Subunit EXO70 is encoded by 23 paralogue genes in genome of Arabidopsis thaliana. Mutation in paralogue subunit EX070H4 causes defect in trichome maturation. Mutant trichomes have thin, not reinforced cell wall, making them soft and elastic. Transcription of EXO70H4 gene is induced by UV radiation, therefore observations of plants cultivated on UV-B radiation were done. Analysis of mutants cultivated on UV-B radiation revealed hyperaccumulation of vesicules in cytoplasm, which were visible by light microscope. Hyperaccumulation was not observed in control plants cultivated on UV-B radiation, but thickening of cell wall was induced. Th is reaction to UV in trichomes hasn't been described yet. Analysis of cellular localization made with YFP tagged constructs revealed that EXO70H4 localizes into mobile corpuscules associating with Golgi apparatus. It was found with yeast two hybrid system that EXO70H4 interacts with TRS120, subunit of tethering complex TRAPPII which is active in Golgi apparatus....
38

Express?o g?nica relacionada ? produ??o de ?leo essencial e avalia??o do metabolismo de Mentha arvensis L. sob diferentes condi??es de cultivo / Gene expression related to production of essential oil and evaluation of Mentha arvensis metabolism under different conditions of cultivation

Souza, Marco Andre Alves de 18 January 2010 (has links)
Submitted by Sandra Pereira (srpereira@ufrrj.br) on 2017-03-30T12:28:08Z No. of bitstreams: 1 2010 - Marco Andre Alves de Souza.pdf: 5657340 bytes, checksum: becf46e090a1ebcc4a731b733c77fb6a (MD5) / Made available in DSpace on 2017-03-30T12:28:08Z (GMT). No. of bitstreams: 1 2010 - Marco Andre Alves de Souza.pdf: 5657340 bytes, checksum: becf46e090a1ebcc4a731b733c77fb6a (MD5) Previous issue date: 2010-01-18 / Conselho Nacional de Desenvolvimento Cient?fico e Tecnol?gico - CNPq / The cultivation of aromatic specimens for obtaining essential oils have great economic importance, mainly by increasing demand in the food, cosmetic and pharmaceutical industry. Brazil is the largest producer of essential oil, however, is what earns less in money value, because, its production is mainly of orange essential oil, with low added value. The essential oil of M. arvensis is rich in menthol (70-80%), a natural products with higher demand in daily life of modern man. Currently, Brazil has become a major importer of menthol which has contributed negatively to the brazilian trade balance. Thus, for the development of this work was chosen to be a specimens of economic interest and social demand, the Mentha arvensis. The purpose of study was to evaluate whether changes in light intensities and different levels of phosphorus promote changes in biomass production and nutrition, with consequences for the biosynthesis of essential oils. We also analyzed the influence of leaf age on the quality of essential oil. To this end, the plant of M. arvensis was grown under the effect of different conditions, which allowed the analysis of the levels of soluble fractions, of photosynthetic pigments, the activities of enzymes related to nitrogen assimilation and the anatomical and histochemical study of trichomes, morphological structure where it is produce the essential oil. The study also included analysis of the expression of genes related to the route of menthol synthesis. The essential oil was obtained by extraction with hydrodestillation in modified Clevenger and the chemical analysis of substances obtained by GC-MS. The Kovats index was used to collaborate in identification of the main substances in essential oil. The results showed that the essential oil quality is determined by physiological conditions and leaf age and that the production is dependent on the synthesis efficiency and density of trichomes on the leaves. In addition, it was found that different concentrations of phosphorus affected some aspects of plant metabolism, which reflected the production of biomass in the soluble fraction, with consequences on production and quality of essential oils. Also showed that variations in light levels affected the expression of six of the eight genes involved in the route of synthesis of menthol, in plants of M. arvensis and that changes in gene expression are probably associated with a transcription factor, which could be acting on the whole pathway. All of this information showed that environmental conditions and / or nutritional affected some aspects of plant metabolism, which reflected the production of biomass, of trichomes and on the expression of genes related to the route of menthol, which reflect on the quality and the production of essential oils / O cultivo de esp?cies arom?ticas para a obten??o de ?leos essenciais tem grande import?ncia econ?mica, principalmente, pela crescente demanda nas ind?strias de alimentos, de cosm?ticos e a farmac?utica. O Brasil ? o maior produtor de ?leo essencial, entretanto, ? o que menos arrecada em valores monet?rios, pois, sua produ??o ? basicamente de ?leo essencial de laranja, com baixo valor agregado. O ?leo essencial de Mentha arvensis L. ? rico em mentol (70-80%), uma dos produtos naturais com maior demanda no dia-a-dia do homem moderno. Atualmente, o Brasil tornou-se um grande importador de mentol o que tem contribu?do negativamente para a balan?a comercial brasileira. Deste modo, para o desenvolvimento deste trabalho escolheu-se a planta M. arvensis. O objetivo do estudo foi avaliar se varia??es nas intensidades luminosas e diferentes concentra??es de f?sforo promovem altera??es na produ??o de biomassa e em aspectos nutricionais, com reflexos na bioss?ntese de ?leos essenciais. Tamb?m foi avaliada a influ?ncia da idade da folha sobre a qualidade do ?leo essencial. Com esta finalidade, a planta de M. arvensis foi cultivada sob o efeito de diferentes condi??es, o que permitiu a an?lise dos teores das fra??es sol?veis, dos pigmentos fotossint?ticos, das atividades das enzimas relacionadas com a assimila??o do nitrog?nio e o estudo histoqu?mico e anat?mico dos tricomas secretores, estrutura morfol?gica onde ? produzido o ?leo essencial. Tamb?m foram realizadas analises da express?o dos genes relacionados com a rota de s?ntese do mentol. O ?leo essencial foi obtido por hidrodestila??o em Clevenger modificado e as analises qu?micas das subst?ncias realizadas por CG/EM. A utiliza??o do ?ndice de Kovats auxiliou na identific??o das principais subst?ncias no ?leo essencial. Os resultados permitiram concluir que a qualidade do ?leo essencial ? determinada pelas condi??es fisiol?gicas e a idade das folhas e que a produ??o ? dependente da efici?ncia de s?ntese e a densidade de tricomas secretores nas folhas. Al?m disso, foi constatado que as diferentes concentra??es de f?sforo afetaram alguns aspectos do metabolismo vegetal, os quais refletiram na produ??o de biomassa, nas fra??es sol?veis, com conseq??ncias na produ??o e qualidade dos ?leos essenciais. Tamb?m, mostraram que varia??es nos n?veis de luminosidade afetaram a express?o de seis entre os oito genes envolvidos com a rota de s?ntese do mentol, em plantas de M. arvensis e que as altera??es na express?o dos genes provavelmente est?o associados a um fator de transcri??o, o qual deve estar atuando sobre toda a rota metab?lica
39

Characterization Of Taxonomically Related Some Turkish Oak (quercus L.) Species In An Isolated Stand: A Morphometric Analysis Approach

Aktas, Caner 01 June 2010 (has links) (PDF)
The genus Quercus L. is represented with more than 400 species in the world and 18 of these species are found naturally in Turkey. Although its taxonomical, phytogeographical and dendrological importance, the genus Quercus is still taxonomically one of the most problematical woody genus in Turkish flora. In this study, multivariate morphometric approach was used to analyze oak specimens collected from an isolated forest (Beynam Forest, Ankara) where Quercus pubescens Willd., Q. infectoria Olivier subsp. boissieri (Reuter) O. Schwarz and Q. macranthera Fisch. &amp / C. A. Mey. ex Hohen. subsp. syspirensis (C.Koch) Menitsky taxa are belonging to section Quercus sensu stricto (s.s.) are found. Additional oak specimens were included in the analysis for comparison. Morphometric study was based on 52 leaf characters such as, distance, angle, and area as well as counted, descriptive and calculated variables. Morphometric variables were calculated automatically by use of landmark and outline data. Random forest classification method was used to select discriminating variables and predict unidentified specimens by use of pre-identified training group. The results of the random forest variable selection procedure and the principal component analysis (PCA) showed that the morphometric variables could distinguish the specimens of Q. pubescens and Q. macranthera subsp. syspirensis mostly based on the overall leaf size and number of intercalary veins while the specimens of Q. infectoria subsp. boissieri were separated from others based on lobe and lamina base shape. Finally, micromorphological observations of abaxial lamina surface have been performed by scanning electron microscope (SEM) on selected specimens which were found useful to differentiate, particularly the specimens of Q. macranthera subsp. syspirensis and its putative hybrids from other taxa.
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Ecology and Evolution of Resistance to Herbivory : Trichome Production in Arabidopsis lyrata

Løe, Geir January 2006 (has links)
In this thesis, I examine variation in occurrence and performance of glabrous and trichome-producing plants of the perennial herb Arabidopsis lyrata. I combine field studies and genetic analysis to (1) examine the function of trichomes as a resistance character in natural populations, (2) compare the magnitude of population differentiation in trichome-production and at putatively neutral marker loci, (3) examine the molecular genetic basis of trichome-production, and (4) quantify the effects of herbivore removal on population growth and relative performance of glabrous and trichome-producing plants. In a survey of 30 populations of A. lyrata in Norway and Sweden, I documented spatiotemporal variation in damage from insect herbivores. With few exceptions, glabrous plants were more damaged by herbivorous insects than trichome-producing plants in polymorphic populations. Damage levels varied substantially among populations and among years. The intensity of herbivory quantified as mean leaf removal to glabrous plants was higher in polymorphic populations than in monomorphic glabrous populations. Within the Swedish range, populations were more strongly differentiated at the locus coding for glabrousness than at eight putatively neutral isozyme loci. This is consistent with the hypothesis that trichome production is subject to divergent selection. A study of the genetic basis of trichome production showed that glabrousness was associated with mutations in an orthologue to GLABROUS1, a regulatory gene known to cause glabrousness in A. thaliana. Comparative data indicate that the genetic basis of glabrousness varies among populations. Experimental removal of insect herbivores in a natural A. lyrata population increased population growth rate and the relative fitness of the glabrous morph. The results suggest that insect herbivory may influence both population dynamics and selection on trichome production in A. lyrata.

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