Huntington’s disease (HD) is a neurodegenerative disorder caused by the inheritance of one mutant copy of the huntingtin gene. Mutant huntingtin protein (mHtt) contains an expanded polyglutamine repeat region near the N-terminus. Cleavage of mHtt releases an N-terminal fragment (N-mHtt) which translocates, and accumulates in the nucleus. Nuclear accumulation of N-mHtt has been directly associated with cellular toxicity. Decreased transcription is among the earliest detected changes that occur in the brains of HD patients and is consistently observed in all animal and cellular models of HD. Transcriptional dysregulation may trigger many of the perturbations that occur later in disease progression and an understanding of the effects of mHtt may lead to strategies to slow the progression of the disease. Current models of N-mHtt-mediated transcriptional dysregulation suggest that abnormal interactions between N-mHtt and transcription factors impair the ability of these transcription factors to associate at N-mHtt-affected promoters and properly regulate gene expression. We tested various aspects of these models using two N-mHtt-affected promoters in in vitro transcription assays and in two cell models of HD using techniques including overexpression of known N-mHtt-interacting transcription factors, chromatin immunoprecipitation, promoter deletion and mutation analyses and in vitro promoter binding assays. Based on our results and those in the literature, we proposed a new model of N-mHtt-mediated transcriptional dysregulation centered on the presence of N-mHtt at affected promoters. We concluded that simultaneous interaction of N-mHtt with multiple binding partners within the transcriptional machinery would explain the gene-specificity of N-mHtt-mediated transcriptional dysregulation, as well as the observation that some genes are affected early in disease progression while others are affected later. Our model explains why alleviating N-mHtt-mediated transcriptional dysregulation through overexpression of N-mHtt-interacting proteins has proven to be difficult and suggests that the most realistic strategy for restoring gene expression across the spectrum of N-mHtt affected genes is by reducing the amount of soluble nuclear N-mHtt.

Adopting a minimalist framework, the dissertation provides an analysis for the syntactic structure of comparatives, with special attention paid to the derivation of the subclause. The proposed account explains how the comparative subclause is connected to the matrix clause, how the subclause is formed in the syntax and what additional processes contribute to its final structure. In addition, it casts light upon these problems in cross-linguistic terms and provides a model that allows for synchronic and diachronic differences. This also enables one to give a more adequate explanation for the phenomena found in English comparatives since the properties of English structures can then be linked to general settings of the language and hence need no longer be considered as idiosyncratic features of the grammar of English. First, the dissertation provides a unified analysis of degree expressions, relating the structure of comparatives to that of other degrees. It is shown that gradable adjectives are located within a degree phrase (DegP), which in turn projects a quantifier phrase (QP) and that these two functional layers are always present, irrespectively of whether there is a phonologically visible element in these layers. Second, the dissertation presents a novel analysis of Comparative Deletion by reducing it to an overtness constraint holding on operators: in this way, it is reduced to morphological differences and cross-linguistic variation is not conditioned by way of postulating an arbitrary parameter. Cross-linguistic differences are ultimately dependent on whether a language has overt operators equipped with the relevant – [+compr] and [+rel] – features. Third, the dissertation provides an adequate explanation for the phenomenon of Attributive Comparative Deletion, as attested in English, by way of relating it to the regular mechanism of Comparative Deletion. I assume that Attributive Comparative Deletion is not a universal phenomenon, and its presence in English can be conditioned by independent, more general rules, while the absence of such restrictions leads to its absence in other languages. Fourth, the dissertation accounts for certain phenomena related to diachronic changes, examining how the changes in the status of comparative operators led to changes in whether Comparative Deletion is attested in a given language: I argue that only operators without a lexical XP can be grammaticalised. The underlying mechanisms underlying are essentially general economy principles and hence the processes are not language-specific or exceptional. Fifth, the dissertation accounts for optional ellipsis processes that play a crucial role in the derivation of typical comparative subclauses. These processes are not directly related to the structure of degree expressions and hence the elimination of the quantified expression from the subclause; nevertheless, they are shown to be in interaction with the mechanisms underlying Comparative Deletion or the absence thereof. / Unter Verwendung eines minimalistischen Frameworks wird in der Dissertation eine Analyse der syntaktischen Struktur von Vergleichskonstruktionen vorgestellt, mit besonderem Augenmerk auf der Ableitung des eingebetteten Satzes. Die vorgeschlagene Analyse erklärt, wie der komparative Nebensatz mit dem Matrixsatz verbunden ist, wie der Nebensatz in der Syntax gebildet wird und welche zusätzlichen Prozesse zu seiner endgültigen Struktur beitragen. Außerdem beleuchtet sie diese Probleme aus cross-linguistischer Sicht und bietet ein Modell, das synchrone und diachrone Unterschiede berücksichtigt. Dies ermöglicht auch eine adäquatere Erklärung der Phänomene in englischen Vergleichskonstruktionen, da die Eigenschaften der englischen Strukturen mit allgemeinen Eigenschaften der Sprache verknüpft werden und es daher nicht mehr nötig ist, sie als idiosynkratrische Merkmale der Grammatik der englischen Sprache zu behandeln. Die Dissertation bietet zum einen eine einheitliche Analyse von Gradphrasen, wobei die Struktur von Vergleichskonstruktionen mit der von anderen Graden verbunden wird. Es wird gezeigt, dass graduierbare Adjektive sich in einer Gradphrase (degree phrase, DegP) befinden, die wiederum eine Quantorenphrase (QP) projiziert, und dass diese beiden Funktionsschichten immer vorhanden sind, unabhängig davon, ob es ein phonologisch sichtbares Element in diesen Schichten gibt. Zweitens präsentiert die Dissertation eine neue Analyse von Komparativ-Tilgung (Comparative Deletion), die auf eine Overtheits-Bedingung für Operatoren reduziert wird: dadurch wird das Phänomen auf morphologische Unterschiede zurückgeführt, und cross-linguistische Variation wird nicht durch die Postulierung eines arbiträren Parameters begründet. Cross-linguistische Unterschiede sind letztlich davon abhängig, ob eine Sprache overte Operatoren mit den relevanten Merkmalen – [+ compr] und [+ rel] – hat. Drittens bietet die Dissertation eine adäquate Erklärung für das Phänomen der attributiven Komparativ-Tilgung (Attributive Comparative Deletion), wie man sie im Englischen findet, indem sie mit dem regulären Mechanismus der Komparativ-Tilgung in Zusammenhang gebracht wird. Ich gehe davon aus, dass attributive Komparativ-Tilgung kein universelles Phänomen ist, und dass ihr Vorhandensein im Englischen durch unabhängige, allgemeinere Regeln erfasst werden kann, während das Fehlen solcher Regeln zur Abwesenheit des Phänomens in anderen Sprachen führt. Viertens erklärt die Dissertation bestimmte Phänomene in Bezug auf diachronische Veränderungen und untersucht, wie Veränderungen im Status der Komparativoperatoren beeinflussen, ob Komparativ-Tilgung in einer Sprache vorkommt: Ich argumentiere dafür, dass nur Operatoren ohne eine lexikalische XP grammatikalisiert werden können. Die zugrunde liegenden Mechanismen sind im Wesentlichen allgemeine Prinzipien der Ökonomie, und damit sind die Prozesse nicht sprachspezifisch oder Ausnahmen. Fünftens bietet die Dissertation eine Erklärung für optionale Ellipsenprozesse, die bei der Ableitung von typischen komparativen Nebensätzen eine entscheidende Rolle spielen. Diese Prozesse haben nicht direkt mit der Struktur von Gradphrasen und somit mit der Entfernung der quantifizierten Phrase aus dem Nebensatz zu tun; aber es wird gezeigt, dass sie mit den Mechanismen, die Komparativ-Tilgung oder deren Abwesenheit zugrunde liegen, interagieren.

String-to-String Correction is the process of transforming some mutable string M into an exact copy of some other string (the target string T), using a shortest sequence of well-defined edit operations. The formal STRING-TO-STRING CORRECTION problem asks for the optimal solution using just two operations: symbol deletion, and swap of adjacent symbols. String correction problems using only swaps and deletions are computationally interesting; in his paper On the Complexity of the Extended String-to-String Correction Problem (1975), Robert Wagner proved that the String-to-String Correction problem under swap and deletion operations only is NP-complete for unbounded alphabets. In this thesis, we present the first careful examination of the binary-alphabet case, which we call Binary String-to-String Correction (BSSC). We present several special cases of BSSC for which an optimal solution can be found in polynomial time; in particular, the case where T and M have an equal number of occurrences of a given symbol has a polynomial-time solution. As well, we demonstrate and prove several properties of BSSC, some of which do not necessarily hold in the case of String-to-String Correction. For instance: that the order of operations is irrelevant; that symbols in the mutable string, if swapped, will only ever swap in one direction; that the length of the Longest Common Subsequence (LCS) of the two strings is monotone nondecreasing during the execution of an optimal solution; and that there exists no correlation between the effect of a swap or delete operation on LCS, and the optimality of that operation. About a dozen other results that are applicable to Binary String-to-String Correction will also be presented. / Graduate / 0984 / 0715 / tspreen@gmail.com

The aim of this thesis is to test two hypotheses. The first one is about the nature of comprehension impairment in Broca&#039 / s aphasia, namely the Trace Deletion Hypothesis (TDH), and the other is about the similarity between child and aphasic language, namely the Regression Hypothesis. According to TDH, agrammatic patients are impaired in comprehension of certain structures that are formed by movement transformation whereas they show normal comprehension in canonical structures. TDH proposes that patients use a default strategy, which assigns the first NP the agent role. As for the Regression hypothesis, children follow a hierarchy while acquiring a language, which is also followed by aphasic patients in the reversed order. That is, what is learnt last is lost first as a result of brain damage. In order to test these two hypotheses, we designed a psycholinguistic test in which the comprehension of Turkish relative clauses is tested via sentence-picture matching task. The same test is applied to children, agrammatic patients, and normal control subjects. We expected that Broca&#039 / s patients would be impaired in their comprehension of subject relative clauses in order for TDH to be confirmed and that children would also exhibit the same impairment as the agrammatic patients in order for the Regression Hypothesis to be supported. The results we obtained were not compatible with the TDH hypothesis in that the patients did not show comprehension deficit in subject relatives but they had problems in object relative clauses, which led us to conclude that TDH did not offer a cross-linguistic explanation for the nature of comprehension deficit in agrammatism and that even if the traces were deleted, the default strategy applied in each language was a parametric feature. We propose that Turkish patients assign the agent role to the first NP that is in the pre-verbal position, which is called the pre-verbal strategy. Also, we hypothesize that the difficulty the Turkish agrammatic patients present might be due to an impairment in another feature, which is agreement morphology rather than the deletion of traces. This study is compatible with the Regression Hypothesis in that both the patients and children exhibited similar impairment in the comprehension of object relative clauses.

Supplementary material to figures contained on DVD only available with manuscript. / Thesis (PhD)--Macquarie University, Division of Environmental & Life Sciences, Dept. of Biological Sciences, 2005. / Bibliography: p. 221-244. / Introduction -- Materials and methods -- Isolation of the hex1 gene from Trichoderma reesei and Ophiostoma floccosum -- Expression of DsRed under the cbh1 promoter and the hex1 promoter with random integration -- Modified expression vectors containing a fusion to a portion of hex1 gene sequence -- Expression of DsRed from the hex1 locus and the phenotypic characteristics of a hex1 deletion mutant -- Summary and concluding discussion. / For Trichoderma reesei to be developed as an effiecient producer of a large variety of proteins, the expression system requires diversification. In particular, the choice of promoters available needs to be broadened to include promoters which are active in conditions other than those conducive to induction of cellulase expression. Using proteomics, the HEX1 protein was identified as an abundant protein of the cell envelope of T. reesei when grown on a range of carbon sources, suggesting that a strong constitutive promoter drives the expression of this physiologically important protein. This thesis is an exploration into the hex1 gene promoter and the role of hex1 in the maintenance of mycelium integrity in T. reesei with consideration for the application of this gene in the further development of filamentous fungi as protein expression systems. -- The single copy hex1 gene and flanking regions were isolated from T. reesei and another biotechnologically important fungus, Ophiostoma floccosum. The fluorescent reporter protein DsRed1-E5 was expressed under the T. reesei hex1 promoter and promoter activity was monitored by fluorescence CLSM and RNA analysis. During the rapid growth phase of a culture, the hex1 promoter was active in a range of carbon sources and three transcipt types with alternative tsp and splicing sites were discovered for the hex1 gene. The distribution of fluorescence throughout the mycelium suggested spatial regulation of the hex1 promoter as well as temporal regulation. The promoter was continually active in the absence of a functional hex1 gene product suggesting that the hex1 promoter is regulated in part, by negative feedback from the endogenous gene product. Interruption of the hex1 gene produced hyphae that leaked excessive volumes of cytoplasm when physically damaged which may be advantageous for the externalisation of selected protein products. The results indicate that the regulation of the hex1 hene promoter is complex and that the hex1 gene is integral to the maintenance of the integrity of the fungal mycelium. / Mode of access: World Wide Web. / xv, 244 p. ill

Diss. (sammanfattning) Linköping : Linköpings universitet, 2009. / Härtill 5 uppsatser.

Made available in DSpace on 2015-05-14T12:43:20Z (GMT). No. of bitstreams: 1 arquivototal.pdf: 608431 bytes, checksum: 180471d1938e53bfb3a283ccaedde7d9 (MD5) Previous issue date: 2009-10-22 / Coordenação de Aperfeiçoamento de Pessoal de Nível Superior / This work had as objective to analyze the process of variation of the lateral postvocalic /l/ in syllabic position of coda in the speech of Araguatins, state of Tocantins. The sample was constituted of interviews of approximately one hour of duration with 36 speakers, divided by sex, age and educational level, we correlate to these extralinguistic variables the structural variables: preceding phonological context, following phonological context, extension of word, position of the lateral and stressing. In the process of computational analysis, through the GOLDVARB, they had been selected by stepping up as relevant, in a hierarchic order, the variables: preceding phonological context, stressing, sex, extension of word, educational level, following phonological context and age. 3256 occurrences had been computed, being 2961 occurrences of the semi-vocalized lateral [w]; e 295 of deletion [Ø]. The presence of posterior vowel, in particular [u], in the Preceding phonological context did not favor, decisively, the implementation of the rule of vocalization of the post-vocalic lateral /l/. Due to the following phonological context, the vowels and the labial consonants had conditioned the deletion, in the other hand the pause was supporter to the vocalization. It was also proven that how much bigger the phonic mass bigger the propensity of the deletion of the lateral, similar situation happens when the lateral is post-tonic syllable. For social variable sex, we can say that men have favored much more the deletion of lateral in comparison with women. In the analysis of the influence of the variable educational level, it became clear that the more educated is the informant more likely occurs the maintenance of semi-vocalized variant of /l/ post-vocalic. The results for age, showed us that there is currently in Araguatins a certain stability in the use of /l/ in in syllabic position of coda in all age groups. / Este trabalho teve como objetivo analisar o processo de variação da lateral pós-vocálica /l/ em posição de coda silábica no falar de Araguatins, estado do Tocantins. A amostra foi constituída de entrevistas de aproximadamente uma hora de duração com 36 informantes, estratificados por sexo, faixa etária e escolaridade, correlacionamos a estas variáveis extralingüísticas as variáveis estruturais: contexto fonológico precedente, contexto fonológico seguinte, extensão do vocábulo, posição da lateral e tonicidade. No processo de análise computacional, através do GOLDVARB, foram selecionadas pelo stepping up como relevantes, numa ordem hierárquica, as variáveis: Contexto fonológico precedente, Tonicidade, Sexo, Extensão do Vocábulo, Escolaridade, Contexto fonológico seguinte e Faixa etária. Foram computadas 3256 ocorrências, sendo 2961 ocorrências da lateral semivocalizada [w]; e 295 de apagamento [Ø]. A presença de vogal posterior, sobretudo [u], no Contexto fonológico precedente desfavoreceu, decisivamente, a implementação da regra de vocalização da lateral pós-vocálica. Quanto ao contexto fonológico seguinte, as vogais e as consoantes labiais condicionaram ao apagamento, enquanto a pausa foi favorecedora à vocalização. Ficou comprovado também que quanto maior a massa fônica maior a propensão do apagamento da lateral, situação semelhante ao que acontece quanto a lateral se apresenta em sílaba postônica. Em relação a variável social Sexo, podemos dizer que os homens favoreceram mais o apagamento da lateral do que as mulheres. Na análise da influência da variável Anos de escolarização, ficou claro que quanto mais escolarizado for o informante mais propenso estará à manutenção da variante semivocalizada do /l/ pós-vocálico. Já os resultados para Idade, mostraram-nos que há, atualmente em Araguatins, uma certa estabilidade no uso feito da lateral em coda silábica em todas as faixas etárias.

Coordenação de Aperfeiçoamento de Pessoal de Nível Superior / Os INDELs são polimorfismos de comprimento, gerados a partir de inserções e/ou deleções de um ou mais nucleotídeos. Os marcadores INDELs, que estão amplamente distribuídos pelo genoma e se caracterizam pela alta estabilidade devido à baixa taxa mutacional (10-9), podem ser analisados a partir da amplificação por PCR (Reação em Cadeia da Polimerase). A facilidade de análise e a possibilidade de construção de sistemas multiplex capazes de gerar amplicons curtos (menores que 100 pb) tornam os INDELs uma importante ferramenta para identificação humana por DNA. Para avaliar a eficiência e validar a metodologia que emprega os polimorfismos de inserção/deleção na identificação humana, utilizamos o sistema Indel-plex ID, capaz de amplificar simultaneamente 38 loci INDELs bialélicos de cromossomos autossomos. Diferentes amostras biológicas (cabelo, saliva, sangue, sêmen e urina) foram genotipadas apresentando reprodutibilidade entre todas as tipagens. A concentração mínima de DNA necessária para amplificação dos 38 loci INDELs foi de 0,5 ng. Artefatos do tipo split peaks foram observados em algumas amostras. Os produtos da PCR foram purificados em resina Sephadex proporcionando melhores condições de análise, redução de artefatos e aumento na intensidade média de fluorescência dos alelos amplificados. A eficiência do sistema Indel-plex ID na amplificação de DNA degradado foi verificada durante as análises das amostras de DNA extraídas de restos mortais (ossos e dentes). Comparativamente ao sistema Identifiler, o Indel-plex ID, se mostrou mais eficiente em termos de número de loci genotipados e qualidade de amplificação. Nas investigações de vínculos genéticos realizadas com o sistema Indel-plex ID foi possível corroborar resultados anteriores obtidos pela análise de marcadores STR. Nas análises com amostras in vivo foram obtidos valores máximos de Probabilidades de Paternidade de 99,99998%. Para casos envolvendo supostos pais falecidos, o sistema Indel-plex ID reforçou resultados obtidos com o sistema Identifiler e Minifiler. A Probabilidade de Paternidade de 99,953%, obtida com o sistema Indel-plex ID, conjugada com a Probabilidade de Paternidade de 99,957%, obtida como o sistema Minifiler, possibilitou um índice final de 99,99998%. Os resultados evidenciaram que os loci INDELs do sistema Indel-plex ID são altamente informativos, constituindo uma ferramenta importante em estudos de identificação humana e de relações de parentesco / INDELs are length polymorphisms, generated from insertions and/or deletions of one or more nucleotides. The INDEL markers, which are widely distributed throughout the genome and characterized by high stability due to their low mutational rate (10-9), can be analyzed based on amplification by PCR (Polimerase Chain Reaction). This ease in being analyzed and the possibility of building multiplex systems capable of generating short amplicons (smaller than 100 pb), render INDELs an important tool for DNA-based human identification. So as to evaluate the efficiency and validate the methodology which makes use of insertion/deletion polymorphisms in human identification, we have employed the Indel-plex ID system, capable of simultaneously amplifying 38 INDEL loci of biallelic autosome chromosomes. Different biological samples (hair, saliva, blood, semen and urine) were genotyped showing reproducibility of all typing. The minimum DNA concentration for the amplification of the 38 INDEL loci is 0,5 ng. Artifacts of the split peaks type were observed in some samples. The purification of the PCRs products in Sephadex resin provided better conditions for analysis, reduction of artifacts and increased the average intensity of allele fluorescence. The efficiency of the Indel-plex ID system in the amplification of degraded DNA was verified in analysis of DNA samples extracted from mortal remains (bones and teeth). In comparison with the Identifiler system, the Indel-plex ID has proven more efficient in terms of the number of genotyped loci and amplification quality. During the investigation of genetic relations, carried out with the Indel-plex ID system, it was possible to corroborate previous results obtained through the analysis of STR markers. In investigations based on in vitro samples, maximum values of 99,99998% in Paternity Probabilities were obtained. In genetic investigations related to deceased supposed parents, the Indel-plex ID system corroborated results obtained with the Identifiler and Minifiler systems. The Paternity Probability of 99,953% obtained with the Indel-plex ID system, allied with the Paternity Probability of 99,957% obtained with the Minifiler rendered possible the final indicator of 99,99998%. The results have made evident that the INDEL loci of the Indel-plex ID system are highly informative and constitute an important tool for studies in both human identification and parenthood relations identification

Submitted by Maike Costa (maiksebas@gmail.com) on 2016-07-27T13:13:05Z No. of bitstreams: 1 arquivo total.pdf: 2055522 bytes, checksum: fc9ebdc72a3c83d2e7dce3ad4e1fd31b (MD5) / Made available in DSpace on 2016-07-27T13:13:05Z (GMT). No. of bitstreams: 1 arquivo total.pdf: 2055522 bytes, checksum: fc9ebdc72a3c83d2e7dce3ad4e1fd31b (MD5) Previous issue date: 2015-10-16 / Reading acquisition is a complex process, which includes several concepts from the simplest and primary such as decoding signs, to the fullest, as we see Martins (2012), Fernandes (2010), who consider reading much more than the simple action of translating language codes. This research used the qualitative method in order to be exploratory, aiming to provide greater familiarity with the problem in order to make it explicit or build hypotheses, involving literature review and analysis of the activities, which encouraged understanding the phenomenon under study. The research also used the technique of observation and systematization of data collection, in order to identify the determinants of the phenomenon, which favor the occurrence of the same.Fieldwork was in a municipal public school in the city of Recife, in Pernambuco. At first there were, initially, six students in this research, but as appropriate to what the research proposed, the number changed to four, this enabled a transformation of the students’ role in the reading classes. The weak points in the learning of the reading process were identified, and the activities with specific reading strategies, that were used as a support to remedy the difficulties presented by the students of the third grade of elementary school 1. Production was analyzed in order to verify whether or not there is the deletion of the coda in /r/, /s/ and /l/medial and final, for language deletion of syllable codas performed in readings. After the intervention process it was found that with the application of consistent reading strategies, participants developed a production of syllabic coda in /r/, /s/ and /l/ medial and final. And identify the degree of complexity of the reading of the focus on students and the reading of the focus on students and the reading level of each student was at the beginning during the process and the final phase of the development of research. / A aquisição da leitura é um processo complexo, o qual contempla várias concepções desde a mais simples e primária como, decodificar signos, até as mais complexas, conforme vemos Martins (2012), Fernandes (2010), que consideram a leitura muito mais do que uma simples ação de tradução da escrita dos códigos linguísticos. Essa pesquisa usou o método qualitativo com objetivo de ser exploratória, visando a proporcionar maior familiaridade com o problema com vistas a torná-lo explícito ou a construir hipóteses, envolvendo também levantamento bibliográfico e análise das atividades, as quais estimularam a compreensão no fenômeno em estudo. A pesquisa usou também a técnica da observação e sistematização de coleta de dados, visando a identificar os determinantes do fenômeno, os quais favorecem para a ocorrência dos mesmos, bem como verificar a questão da variação na pronúncia das Codas silábicas /R/, /L/ e /S/ em palavras, frases, imagens e textos , especificamente nas questões de produção e apagamento. A pesquisa de campo foi em uma Escola Municipal da Rede pública da cidade do Recife, em PE. Participaram desta pesquisa seis estudantes. A mesma possibilitou uma transformação na atuação dos alunos nas aulas de leitura. Foram identificados os pontos de fragilidade na aprendizagem do processo de leitura, bem como ofereceu atividades com específicas estratégias de leitura, que serviram de suporte para sanar as dificuldades apresentadas pelos estudantes do 3º ano do Ensino Fundamental I. A escolha dessa temática emergiu da nossa inquietação enquanto profissionais da área de educação, pois como educadores sentíamos incomodados com a falta da produção das Codas silábicas nas leituras realizadas pelos estudantes, fato que motivou o presente estudo. Nesta pesquisa, utilizamos os aportes teóricos de autores que focam na definição do ato de ler e nas suas especificidades - Fernandes (2010), Kleiman (1989), Koch & Elias (2006) e Martins (2012), bem como autores que primam pela abordagem das estratégias de leitura, como é o caso de Solé (1998). No tocante à temática da Sílaba e Coda Silábica, tomamos como aparato teórico-metodológico os referenciais de Hora (2006). Foi analisada a produção de leitura dos alunos com vistas a verificar se ocorre ou não o apagamento da coda silábica em /R/, /S/ e /L/ mediais e finais, por meio de imagens palavras, frases e textos. No início da pesquisa identificamos grande apagamento das Codas silábicas nas leituras realizadas. Após o processo de intervenção foi constatado que com a aplicação das estratégias de leitura coerentes, os participantes desenvolveram a produção das Codas silábicas em /R/, /S/ e /L/ mediais e finais. Bem como identificamos o grau de complexidade da leitura dos alunos em foco, e o nível de leitura em que cada aluno se encontrava no início, durante e fase final do desenvolvimento da pesquisa.

Made available in DSpace on 2015-03-26T13:51:54Z (GMT). No. of bitstreams: 1 texto completo.pdf: 4267302 bytes, checksum: e9b9d7cbe9f5e7cfd714ca533302e571 (MD5) Previous issue date: 2011-02-18 / Conselho Nacional de Desenvolvimento Científico e Tecnológico / Colletotrichum lindemuthianum is the causal agent of common bean antracnose. This fungus, like other phytopatogens, is constantly exposed to several toxic compounds from many sources, what makes indispensable the development of protection strategies against these products. One of these strategies is related to membrane transporters proteins like the Major Facilitator Superfamily (MFS), that could provide protection against toxic compounds or minimizing its action, being essential for the fungal cellular viability maintenance. In this context, this work aimed to inactivate the mfs1 gene encoding a MFS membrane transporter and investigate the phenotypic alterations entailed in an isolate C. lindemuthianum mutant LV49 (race 89) for this gene. To obtain the mutant, it was necessary to confirm if mfs1 gene was organized as a single copy in the C. lindemuthianum genome. The mfs1 gene can be organized in a cluster in view that a second open reading frame, which corresponds to a transcription factor superfamily containing a Zn2-Cys6 domain, identified as clft1, was observed in 3` downstream region of this gene. The mfs1 promoter analysis revealed a putative mfs1 element that is recognized by proteins of this family, what suggests that this protein could be related to the mfs1 expression regulation. The Split-Marker technique proved to be efficient in C. lindemuthianum mfs1 gene inactivation enabling the study of mfs1 function in a mutant by specific integrations without ectopic integrations. The Δmfs1 mutant showed no differences in drug sensibility profile when commonly drugs employed in antracnose control was used and in relation to pathogenicity, the mutant symptoms started earlier on susceptible bean leaves, showing a stress situation due to the genic product absence. It was also observed that mfs1 presents a primordial role in C. lindemuthianum cellular viability maintenance, what was confirmed by the altered conidiation observed, confirming that this gene encodes for a specific hexose membrane transporter, specifically carbon sources like glucose, mannose and fructose. The protein Mfs1 phylogenetic analysis allow us to conclude that this transporter is a SP family member and the MFS proteins are strongly related with the transported substance. Studies conducted with MFS transporters are important to broaden the knowledge of these proteins and to understand the cell viability in C. lindemuthianum. / O fungo Colletotrichum lindemuthianum é o agente causal da antracnose do feijoeiro comum. Este fungo, assim como outros fungos fitopatógenos estão constantemente expostos a uma grande variedade de compostos tóxicos provenientes de várias fontes, o que torna imprescindível para estes o desenvolvimento de mecanismos de proteção contra estes produtos. Uma dessas estratégias está relacionada com a presença de proteínas transportadoras de membrana, como as pertencentes à Principal Superfamília Facilitadora (MFS), que podem fornecer aos fungos proteção contra compostos tóxicos evitando ou minimizando a ação destes, sendo em sua maioria essenciais para a manutenção da viabilidade celular. Este trabalho teve como objetivo inativar o gene mfs1 que codifica para um transportador de membrana da família MFS e investigar as alterações fenotípicas ocasionadas em um mutante C. lindemuthianum isolado LV49 (raça 89) para este gene. Para a obtenção do mutante foi necessário confirmar que o gene mfs1 encontrava-se presente em cópia única no genoma de C. lindemuthianum. O gene mfs1 pode estar organizado em um conjunto de genes com funções relacionadas, uma vez que downstream à região 3’ deste foi identificada uma segunda janela aberta de leitura correspondente a uma proteína da superfamília de fatores de transcrição contendo o domínio Zn2-Cys6, identificado como clft1. A análise do promotor do gene mfs1 revelou um putativo cis elemento de reconhecimento por proteínas desta família, o que sugere que esta proteína possa estar relacionada à regulação da expressão de mfs1. A técnica de Split- Marker mostrou-se eficiente na inativação do gene mfs1 de C. lindemuthianum, possibilitando o estudo da função do gene mfs1, em um mutante com integração específica e livre de integrações ectópicas. O mutante Δmfs1 não mostrou diferenças no perfil de sensibilidade a drogas comumente empregadas no controle da antracnose e em relação à patogenicidade, o mutante induziu mais precocemente os sintomas em folhas de feijoeiro susceptível, evidenciando uma situação de estresse decorrente da ausência do produto gênico. Foi observado também que o gene mfs1 exerce um papel primordial na manutenção da viabilidade celular de C. lindemuthianum, fato este confirmado pela conidiação alterada e pela confirmação de que este gene codifica para um transportador de membrana específico no transporte de hexoses, especificamente glicose, manose e frutose, uma vez que o mutante Δmfs1 mostrou crescimento reduzido quando cultivado em meios contendo apenas glicose, manose e frutose como fontes de carbono. A análise filogenética da proteína Mfs1 associada aos outros resultados obtidos nos sugere que este transportador é um membro da família SP, e que as proteínas MFS estão fortemente relacionadas com o tipo de substância que é transportada. Estudos de natureza básica sobre transportadores MFS são importantes para ampliar os conhecimentos sobre estas proteínas e a viabilidade celular em C. lindemuthianum.