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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.
251

Mikrobiální společenstva a metagenom průmyslově znečištěných půd: výskyt genů kódujících AEH / Microbial consortia and metagenome of industrially polluted soil: occurrence of genes encoding AEH

Pitkina, Anastasiya January 2015 (has links)
Soils contain highly diverse consortia of bacteria making them very attractive starting points for both culture-dependent and metagenomic discovery efforts. The present diploma thesis analyses the composition of the microbial community from pharmaceutically polluted soil, with the employment of next-generation Illumina sequencing of 16S rDNA region. This analysis revealed high complexity of the soil microbial environment and confirmed that anthropogenic activity (represented by production of beta- lactam antibiotics) influences the variability and abundance of the species, yet without reducing the microbial diversity. In the second part of the thesis, isolation and heterologous expression of a novel gene encoding alpha-amino acid ester hydrolase (AEH) from a cultivable soil microorganism B. cereus is described. AEHs possess industrial potential for biocatalytic synthesis of semi-synthetic beta-lactam antibiotics, which are presently of great clinical importance. Powered by TCPDF (www.tcpdf.org)
252

Clonagem, expressão e avaliação da imunogenicidade e do potencial adjuvante induzidos pela proteína \"heat-shock\"  Cpn60 da Bordetella pertussis. / Molecular cloning, expression and evaluation of immunogenicity and adjuvant potential induced from the heat-shock protein Cpn60 from Bordetella pertussis.

Wolf, Paulo Silva 06 May 2010 (has links)
A proteína Cpn60 faz parte de um grupo de proteínas altamente conservadas que estão envolvidas em funções celulares essenciais. camundongos BALB\\c foram imunizados com 5 ou 10 µg da proteína recombinante (Cpn60r) sozinha ou adicionada à vacina DTP sem hidróxido de alumínio (NADTP). A vacina DTP do Instituto Butantan (DTP) foi usada como controle. Foi avaliada a produção de citocinas por células esplênicas após reestímulo in vitro com a Cpn60r. Os animais foram desafiados após o protocolo de imunização. A Cpn60r sozinha ou misturada à vacina NADTP foi capaz de induzir níveis de anticorpos contra pertussis mais altos do que os induzidos pela DTP. Os níveis de IgG1 e IgG2a foram similares para todos os grupos. Pôde-se observar a produção de de IL-6 e IFN-&#947 nos grupos imunizados com Cpn60r. Os grupos imunizados com Cpn60r+NADTP apresentaram um índice de proteção entre 60 e 80% contra o desafio pela bactéria virulenta, semelhante ao grupo imunizado com DTP. A proteína Cpn60r é bastante promissora não somente como imunógeno, mas também como adjuvante. / The Cpn60 protein is a member of a group of higly conserved proteins linked to essencial cell functions. The Cpn60 was cloned, expressed and its immune response has been evaluated. BALB\\c mice were immunized with 5 or 10 µg of the recombinant protein (Cpn60r) alone or mixed with DPT vaccine without aluminum hidroxyde (NADPT). The DPT vaccine from Instituto Butantan was used as control. We evaluated the cytokines production by spleen cells after they have been reestimulated in vitro with Cpn60r. The animals were challenged after the immunization protocol. The Cpn60r alone or mixed with NADPT vaccine was able to induce higher antibodies levels than DPT. IgG1 and IgG2a levels were similar in all groups. We could detect levels of IL-6 and IFN-&#947 on groups immunized with Cpn60r. The groups immunized with Cpn60r+NADTP showed a 60 and 80% protection rate against the challenge with the live bacteria, similar to the group immunized with DPT. These results show the immune response of the recombinant protein that could be included in immunization protocols for pertussis.
253

Clonagem e análise da expressão do fator de transcrição Scratch2 durante a embriogênese inicial de galinha. / Cloning and expression analysis of the transcription factor Scratch2 during the chicken early embryogenesis.

Vieceli, Felipe Monteleone 23 November 2009 (has links)
Em invertebrados, os genes Scratch (Scrt) codificam fatores de transcrição que promovem a neurogênese durante o desenvolvimento. A função de Scrt em vertebrados é desconhecida, mas em camundongos Scrt1 e Scrt2 são especificamente expressos em neurônios pós-mitóticos no embrião e no sistema nervoso central adulto. Neste trabalho, nós clonamos a sequência codificante de Scrt2 de galinha (cScrt2) e caracterizamos seu padrão de expressão no embrião por PCR quantitativo e hibridação in situ. A sequência codificante completa foi clonada no vetor de expressão pMES-GFP e o produto previsto da tradução é uma proteína com 276 aminoácidos. A sequência de aminoácidos compartilha identidades de 70% com Scrt2 de rato e 58% com Scrt de zebrafish. Transcritos cScrt2 são detectados primeiramente na periferia do tubo neural do rombencéfalo em HH 15 e da medula espinhal em HH 17, coincidindo com os locais onde alguns dos primeiros neurônios se diferenciam durante a embriogênese. Entre HH 19-23, a expressão no domínio motor da medula espinhal se concentra progressivamente na interface entre as zonas ventricular e do manto. Além disso, a expressão de cScrt2 também é observada nos gânglios da raíz dorsal a partir de HH 22-23, principalmente no domínio dorsomedial. O campo de expressão de cScrt2 no tubo neural é complementar aos de Notch1, que é expresso em células-tronco neurais, e SCG10, marcador de neurônios diferenciados. Nossos resultados sugerem que durante a embriogênese da medula espinhal cScrt2 é especificamente expresso em neurônios pós-mitóticos indiferenciados. A construção pMES-GFP(cScrt2) possibilita futuras análises funcionais diretas por interferência gênica no embrião de galinha, que serão de grande valor para um melhor entendimento da função dos genes Scrt em vertebrados. / In invertebrates, the Scratch (Scrt) genes encode transcription factors that promote neurogenesis during development. The Scrt function in vertebrates is unknown, but in mice Scrt1 and Scrt2 are specifically expressed in post-mitotic neurons in the embryo and in the adult central nervous system. In this work, we have cloned the coding sequence of chicken Scrt2 (cScrt2) and characterized its expression pattern in the embryo with quantitative PCR and in situ hybridization. The complete coding sequence was cloned in the expression vector pMES-GFP and the predicted translation product is a 276-aminoacids protein. The aminoacid sequence shares identities of 70% with rat Scrt2 and 58% with zebrafish Scrt. cScrt2 transcripts are firstly detected in the periphery of the neural tube in the hindbrain by HH 15 and in the spinal cord by HH 17, coinciding with the places where some of the first neurons differentiate during embryogenesis. Between HH 19-23, the expression in the motor domain of the spinal cord is progressively concentrated in the interface between the ventricular and mantle zones. Furthermore, cScrt2 expression is also observed in the dorsal root ganglia after HH22-23, particularly in the dorsomedial domain. The expression pattern of cScrt2 in the neural tube is complementary to that of Notch1, which is expressed in neural stem cells, and SCG10, a marker for differentiated neurons. Our results suggest that during embryogenesis cScrt2 is specifically expressed in post-mitotic undifferentiated neurons. The construction pMES-GFP(cScrt2) makes possible future direct functional analysis by genetic interference in the chick embryo, which will be of great value for better understanding the Scrt genes function in vertebrates.
254

Clonagem, expressão e avaliação da imunogenicidade e do potencial adjuvante induzidos pela proteína \"heat-shock\"  Cpn60 da Bordetella pertussis. / Molecular cloning, expression and evaluation of immunogenicity and adjuvant potential induced from the heat-shock protein Cpn60 from Bordetella pertussis.

Paulo Silva Wolf 06 May 2010 (has links)
A proteína Cpn60 faz parte de um grupo de proteínas altamente conservadas que estão envolvidas em funções celulares essenciais. camundongos BALB\\c foram imunizados com 5 ou 10 µg da proteína recombinante (Cpn60r) sozinha ou adicionada à vacina DTP sem hidróxido de alumínio (NADTP). A vacina DTP do Instituto Butantan (DTP) foi usada como controle. Foi avaliada a produção de citocinas por células esplênicas após reestímulo in vitro com a Cpn60r. Os animais foram desafiados após o protocolo de imunização. A Cpn60r sozinha ou misturada à vacina NADTP foi capaz de induzir níveis de anticorpos contra pertussis mais altos do que os induzidos pela DTP. Os níveis de IgG1 e IgG2a foram similares para todos os grupos. Pôde-se observar a produção de de IL-6 e IFN-&#947 nos grupos imunizados com Cpn60r. Os grupos imunizados com Cpn60r+NADTP apresentaram um índice de proteção entre 60 e 80% contra o desafio pela bactéria virulenta, semelhante ao grupo imunizado com DTP. A proteína Cpn60r é bastante promissora não somente como imunógeno, mas também como adjuvante. / The Cpn60 protein is a member of a group of higly conserved proteins linked to essencial cell functions. The Cpn60 was cloned, expressed and its immune response has been evaluated. BALB\\c mice were immunized with 5 or 10 µg of the recombinant protein (Cpn60r) alone or mixed with DPT vaccine without aluminum hidroxyde (NADPT). The DPT vaccine from Instituto Butantan was used as control. We evaluated the cytokines production by spleen cells after they have been reestimulated in vitro with Cpn60r. The animals were challenged after the immunization protocol. The Cpn60r alone or mixed with NADPT vaccine was able to induce higher antibodies levels than DPT. IgG1 and IgG2a levels were similar in all groups. We could detect levels of IL-6 and IFN-&#947 on groups immunized with Cpn60r. The groups immunized with Cpn60r+NADTP showed a 60 and 80% protection rate against the challenge with the live bacteria, similar to the group immunized with DPT. These results show the immune response of the recombinant protein that could be included in immunization protocols for pertussis.
255

Cloning and Characterisation of the Human SinRIP Proteins

Schroder, Wayne Ashley, n/a January 2003 (has links)
This thesis describes the cloning and characterisation of a novel human gene and its protein products, which have been designated SAPK- and Ras-interacting protein (SinRIP). SinRIP shares identity with JC310, a partial human cDNA that was previously identified a candidate Ras-inhibitor (Colicelli et al., 1991, Proc Natl Acad Sci USA 88, p. 2913). In this study, it was shown that SinRIP is a member of an orthologous family of proteins that is conserved from yeast to mammals and contains proteins involved in Ras- and SAPK-mediated signalling pathways. Comparison of this family of proteins showed that human SinRIP contains a potential Ras-binding domain (RBD; residues 279-354), a PH-like domain (PHL; 376-487), and a highly conserved novel region designated the CRIM (134-265). Several other potential targeting sites, such as nuclear localisation signals and target sites for kinases, were identified within the SinRIP sequence. The human SinRIP gene is unusually large (>280 kbp) and is located on chromosome 9 at 9q34. SinRIP mRNA was detected in a wide variety of tissue-types and cell lines by RT-PCR, and the SinRIP sequences in the EST database were derived from an diverse array of tissues, suggesting a widespread or ubiquitous expression. Northern blot analysis revealed the highest levels in skeletal muscle and heart tissue. However, the steady-state levels of SinRIP mRNA vary greatly from cell to cell, and SinRIP expression is likely to be regulated at multiple post-transcriptional levels. It was shown that SinRIP mRNA is likely to be translated inefficiently by the normal cap-scanning mechanism, due to the presence of a GC-rich and structured 5’-UTR, which also contains upstream ORFs. Alternative polyadenylation signals in the SinRIP 3’-UTR can be used, resulting in the expression of short and long SinRIP mRNA isoforms. Several potential A/T-rich regulatory elements were also identified in SinRIP mRNA, which may target specific SinRIP mRNA isoforms for rapid degradation. Importantly, it was shown that SinRIP mRNA is alternatively spliced, resulting in the production of distinct SinRIP protein isoforms. Three isoforms, SinRIP2-4, were definitively identified by RT-PCR and full-length cloning. The SinRIP isoforms contain deletions in conserved regions, and are likely to have biochemical characteristics that are different to full-length SinRIP1. SinRIP2 is C-terminally truncated and lacks the PHL domain and part of the RBD, and relatively high levels of SinRIP2 expression arelikely to occur in kidneys. The RBD is disrupted in SinRIP3, but all other domains are intact, and RT-PCR analyses suggest that SinRIP3 is present in some cells at levels comparable to SinRIP1. A rabbit polyclonal antiserum against SinRIP was generated and detected endogenous SinRIP proteins. Using the anti-SinRIP antibody in immunoblots, multiple SinRIP isoforms were observed in most cell types. SinRIP1 and another endogenous SinRIP protein, likely to be SinRIP3, were detected in most cell lines, and appear to be are the major SinRIP proteins expressed in most cells. The subcellular localisation of both recombinant and endogenous SinRIP proteins was investigated by immunofluorescence assays and biochemical fractionation. Recombinant SinRIP1 protein was found in the cytoplasm and associated with the plasma membrane. In contrast, the SinRIP2 protein was predominantly nuclear, with only low-level cytoplasmic staining observed. The endogenous SinRIP proteins, likely to comprise these and other SinRIP isoforms, were found in both the nucleus and cytoplasm. SinRIP1 interacted with GTP-bound (active) Ras, but not GDP-bound (inactive) Ras, in an in vitro assay, and also co-localised with activated H- and K-Ras in cells. The binding profile observed is typical of Ras-effectors, and SinRIP did not inhibit signalling by the Ras proteins, suggesting that it is not likely to be a Ras-inhibitor. It was also shown that SinRIP1 and SinRIP2 both interact and colocalise with c-Jun NH2- terminal kinase (JNK). Both SinRIP proteins were able to recruit JNK to their respective sub-cellular compartments. These interactions suggest an adaptor role for SinRIP in the Ras and/or JNK pathways. In addition, Sam68 was isolated as a SinRIP-binding protein in a yeast two-hybrid screen. Sam68 was shown to colocalise with SinRIP2 and endogenous SinRIP proteins, but not SinRIP1. Further colocalisation studies showed that endogenous SinRIP proteins localise in nuclear structures that may be associated with pre-mRNA splicing. Likely functions for SinRIP, as indicated by experimental results and studies of the orthologues of SinRIP in other species, are discussed.
256

Enhancing gain from long-term forest tree breeding while conserving genetic diversity /

Rosvall, Ola, January 1900 (has links) (PDF)
Diss. (sammanfattning) Umeå : Sveriges lantbruksuniv. / Härtill 4 uppsatser.
257

Avaliação clínica e microbiológica periodontal de crianças e adolescentes sob terapia ortodôntica com aparelhos fixos ou removíveis /

Rêgo, Rodrigo Otávio Citó César. January 2004 (has links)
Orientador: Joni Augusto Cirelli / Banca: José Eduardo Cezar Sampaio / Banca: Ary dos Santos Pinto / Banca: Maria Mônica Studart Gurgel Mendes Moreira / Banca: Márcia Pinto Alves Mayer / Resumo: O objetivo deste estudo foi avaliar os parâmetros clínicos e microbiológicos periodontais de crianças e adolescentes sob terapia ortodôntica com aparelho fixo ou removíveis. Trinta indivíduos (14,5l1,7 anos - Grupo FIX) que utilizavam aparelhos fixos e 18 que utilizavam aparelho extra bucal removível ou placa de Hawley há pelo menos 6 meses (9,6 l 1,5 anos - Grupo REM) foram comparados a dois grupos controle, constituídos por indivíduos da mesma idade (14,2 l 1,7 anos - Grupo C-FIX e 9,3 l 1,9 anos - Grupo C-REM) que não utlizavam esses dispositivos. Foi analisada a presença de placa bacteriana visível (IP), sangramento gengival (IG), profundidade de sondagem (PS) e perda de inserção clínica (PIC). Amostras de placa bacteriana subgengival foram coletadas e analisadas por meio de sondas de oligonucleotídeos para A. actinomycetemcomitans (Aa), C. rectus, Capnocytophaga sp. E. corrodens, F. nucleatum, F. vincentii, M. micros, Neisseriaceae., P. gingivalis, P. intermedia, espiroquetas, T. forsythensis e Treponema sp. Diferenças significantes (p<0,05) foram observadas entre os grupos FIX e C-FIX quanto aos parâmetros IP (66,8% e 47,7%), IG (43% e 15,6%), e para as prevalências de todas as bactérias avaliadas, exceto as da familia Neisseriaceae. Entre dentes bandados e seus análogos no grupo controle foram encontradas diferenças significantes para os parâmetros PV (80,3% e 58,8%), SM (64,3% e 20,6%) e PS (2,9 mm e 2,5 mm), respectivamente. Entre os grupos REM e C-REM, essas diferenças também foram observadas para IP (58,7% e 14,3%) e IG (19,8% e 8,8%) e para as prevalências de Aa, C. rectus, E. corrodens, Neisseriaceae e espiroquetas. Entre os dentes retentores de grampo e seus análogos no grupo controle verificou-se diferenças significantes para IP (77,8% e 31,3%). Não foi verificado aumento da PS associado a PIC. Também foi avaliada a... (Resumo completo, clicar acesso eletrônico abaixo). / Abstract: The purpose of this study was to compare clinical and microbiological parameters in children and adolescents with and without fixed or removable orthodontic appliances. Thirty subjects (mean age 14.5l1.7 years) treated with fixed appliances and 18 treated with removable appliances for at least 6 months were selected as test groups, FIX and REM, respectively. The control groups were comprised of 30 subjects (mean age 14.2l1.7 years - Group C-FIX) and 18 subjects (mean age 9.3l1.9 years - Group C-REM) that did not receive orthodontic treatment. Clinical evaluations were made for plaque index (PI), gingival index (GI), probing depth (PD) and clinical attachment loss (CAL). Subgingival plaque samples were collected from the patients and analyzed by oligonucleotide probes for the presence of A. actinomycetemcomitans (Aa), C. rectus, Capnocytophaga sp. E. corrodens, F. nucleatum, F. vincentii, M. micros, Neisseriaceae., P. gingivalis, P. intermedia, spirochetes, T. forsythensis and Treponema sp. Additionally, two subgingival dental plaque samples from one subject of each test group were further analyzed by cloning and sequencing the amplified 16S rDNA. Significant differences were noted between FIX and C-FIX for PI (66.8% versus 47.7%), GI (43.8% versus 15.6%) and between the banded teeth in the FIX group and the analogous teeth in the C-FIX group for PI (80.3% versus 58.8%), GI (64.3% versus 20.6%) and PD (2.9 mm versus 2.5 mm). Significant differences were noted between FIX and C-FIX for all targeted bacteria but Neisseriaceae. Results: Significant differences were also noted between REM and C-REM for PI (58.7% versus 14.3%) and GI (19.8% versus 8.8%) and between the clasped teeth in the test group and the analogous teeth in the control group for PI (77.8% versus 31.3%). Significant differences were noted between the REM and C-REM for Aa... (Complete abstract, click electronic address below). / Doutor
258

Estudo filogenético de populações de Ceratobasidium noxium, agente causal do mal-do-fio do caqui (Diospyrus kaki) e do chá (Camellia sinensis) no Estado de São Paulo, patogenicidade cruzada e reação de variedades de caqui ao patógeno

Souza, Elaine Costa [UNESP] 18 July 2006 (has links) (PDF)
Made available in DSpace on 2014-06-11T19:29:44Z (GMT). No. of bitstreams: 0 Previous issue date: 2006-07-18Bitstream added on 2014-06-13T20:19:58Z : No. of bitstreams: 1 souza_ec_me_ilha.pdf: 505202 bytes, checksum: b2e8a6c8e22a5805a00f3381be5d40df (MD5) / Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES) / O mal-do-fio (ou queima-do-fio) é uma doença causada pelo fungo Basidiomiceto Ceratobasidium sp., que afeta diversas plantas frutíferas nativas ou cultivadas. A doença ocorre com mais freqüência em zonas de alta precipitação e temperaturas elevadas, típicas de regiões de florestas tropicais como a Amazônia e a Mata Atlântica. Em São Paulo, recentemente detectou-se a ocorrência do mal-do-fio, em caquizeiro na região de Mogi das Cruzes. Essa doença pode- se tornar importante com a expansão do cultivo de fruteiras no Estado. A maioria das pesquisas sobre o patossistema focalizou a epidemiologia e o controle do fungo. Entretanto a etiologia do patógeno ainda não está totalmente definida, especialmente para populações do fungo infectando caqui e chá no Estado de São Paulo. Há também pouca informação sobre a divergência genética entre populações do patógeno de hospedeiros distintos como caqui e chá. O primeiro objetivo deste trabalho foi determinar o posicionamento filogenético global de populações de Ceratobasidium sp. do caqui e do chá, em relação a espécies de Ceratobasidium sp. descritas no mundo. Foram analisadas seqüências de DNA da região ITS-5.8S do rDNA, inferindo-se a história dos alelos ou haplótipos deste lócus, por meio de métodos filogenéticos, cladísticos e coalescentes. Observou-se que uso de C. noxium é apropriado para denominar espécies associadas ao mal-do- fio em caqui e chá, apesar de C. noxium do caqui e do chá constituírem populações filogeneticamente independentes, as quais denominamos de Grupo Diospyrus e Grupo Camellia. Este estudo trouxe uma contribuição importante para a compreensão das relações filogenéticas e biologia de populações de C. noxium em caqui e chá. Uma vez esclarecidas as questões filogenéticas, o segundo objetivo deste trabalho foi testar a patogenicidade cruzada de... / The white-thread blight is a disease caused by the Basidiomycete fungus Ceratobasidium sp. that affects several native or cropped tree fruits. This disease frequently occurs in zones of high precipitation and high temperatures typical of the tropical forest regions such as the Amazon and the Atlantic Forest. In São Paulo, the occurrence of the white-thread blight was detected only recently on kaki orchards closer to Mogi das Cruzes. That disease can become important with the expansion of the fruit trees cropping areas in the State. Most of the researches about the pathosystem has focused on the epidemiology and control of fungus. However the etiology of the pathogen is not totally defined yet, especially for the fungus populations infecting kaki and tea in São Paulo State. There is also little information available about the biological and genetic divergence between pathogen populations from distinct hosts, such as kaki and tea. The first objective of this research was to determine the global phylogenetic placement of populations of Ceratobasidium from kaki and tea, considering the species of Ceratobasidium described throughout the world. Sequences of the ITS-5.8S region of the rDNA were analyzed, inferring the alleles or haplotypes history for this locus, by phylogenetics, cladistisc and coalescent methods. We observed that the use of C. noxium is appropriate to denominate the fungus species associate with the white-thread blight on kaki and tea, despite the fact that C. noxium from kaki and tea constitutes phylogenetically independent populations, which we denominate Diospyrus and Camellia groups. This study brought an important contribution for the understanding of the phylogenetics and population biology of C. noxium infecting kaki and tea. Once the phylogenetics subjects have been cleared, the second objective of this work was to test the cross-pathogenicity... (Complete abstract, access electronic address below)
259

Clonagem e análise da expressão do fator de transcrição Scratch2 durante a embriogênese inicial de galinha. / Cloning and expression analysis of the transcription factor Scratch2 during the chicken early embryogenesis.

Felipe Monteleone Vieceli 23 November 2009 (has links)
Em invertebrados, os genes Scratch (Scrt) codificam fatores de transcrição que promovem a neurogênese durante o desenvolvimento. A função de Scrt em vertebrados é desconhecida, mas em camundongos Scrt1 e Scrt2 são especificamente expressos em neurônios pós-mitóticos no embrião e no sistema nervoso central adulto. Neste trabalho, nós clonamos a sequência codificante de Scrt2 de galinha (cScrt2) e caracterizamos seu padrão de expressão no embrião por PCR quantitativo e hibridação in situ. A sequência codificante completa foi clonada no vetor de expressão pMES-GFP e o produto previsto da tradução é uma proteína com 276 aminoácidos. A sequência de aminoácidos compartilha identidades de 70% com Scrt2 de rato e 58% com Scrt de zebrafish. Transcritos cScrt2 são detectados primeiramente na periferia do tubo neural do rombencéfalo em HH 15 e da medula espinhal em HH 17, coincidindo com os locais onde alguns dos primeiros neurônios se diferenciam durante a embriogênese. Entre HH 19-23, a expressão no domínio motor da medula espinhal se concentra progressivamente na interface entre as zonas ventricular e do manto. Além disso, a expressão de cScrt2 também é observada nos gânglios da raíz dorsal a partir de HH 22-23, principalmente no domínio dorsomedial. O campo de expressão de cScrt2 no tubo neural é complementar aos de Notch1, que é expresso em células-tronco neurais, e SCG10, marcador de neurônios diferenciados. Nossos resultados sugerem que durante a embriogênese da medula espinhal cScrt2 é especificamente expresso em neurônios pós-mitóticos indiferenciados. A construção pMES-GFP(cScrt2) possibilita futuras análises funcionais diretas por interferência gênica no embrião de galinha, que serão de grande valor para um melhor entendimento da função dos genes Scrt em vertebrados. / In invertebrates, the Scratch (Scrt) genes encode transcription factors that promote neurogenesis during development. The Scrt function in vertebrates is unknown, but in mice Scrt1 and Scrt2 are specifically expressed in post-mitotic neurons in the embryo and in the adult central nervous system. In this work, we have cloned the coding sequence of chicken Scrt2 (cScrt2) and characterized its expression pattern in the embryo with quantitative PCR and in situ hybridization. The complete coding sequence was cloned in the expression vector pMES-GFP and the predicted translation product is a 276-aminoacids protein. The aminoacid sequence shares identities of 70% with rat Scrt2 and 58% with zebrafish Scrt. cScrt2 transcripts are firstly detected in the periphery of the neural tube in the hindbrain by HH 15 and in the spinal cord by HH 17, coinciding with the places where some of the first neurons differentiate during embryogenesis. Between HH 19-23, the expression in the motor domain of the spinal cord is progressively concentrated in the interface between the ventricular and mantle zones. Furthermore, cScrt2 expression is also observed in the dorsal root ganglia after HH22-23, particularly in the dorsomedial domain. The expression pattern of cScrt2 in the neural tube is complementary to that of Notch1, which is expressed in neural stem cells, and SCG10, a marker for differentiated neurons. Our results suggest that during embryogenesis cScrt2 is specifically expressed in post-mitotic undifferentiated neurons. The construction pMES-GFP(cScrt2) makes possible future direct functional analysis by genetic interference in the chick embryo, which will be of great value for better understanding the Scrt genes function in vertebrates.
260

Expression studies of human coronavirus nl63- nucleocapsid, membrane and envelope proteins

Manasse, Taryn-lee January 2013 (has links)
>Magister Scientiae - MSc / Acute respiratory infections (ARI) continue to be the leading cause of acute illnesses worldwide and remain the most important cause of infant and young children mortality. Many viruses such as rhinoviruses, influenza viruses, parainfluenza viruses, respiratory syncytial viruses, adenoviruses and coronaviruses are deemed to be the etiological agents responsible for ARI’s in children. The recently discovered coronaviruses HCoV-HKU1 and HCoV-NL63 contribute significantly to the hospitalization of children with ARI’s. HCoV-NL63 was first identified in 2004, as the pathogen responsible for the hospitalization of a 7 month old child presenting with coryza, conjunctivitis and fever. Since then a significant amount of knowledge has been gained in the clinical spectrum on this virus, however HCoV-NL63 is still not well characterized on the molecular and proteomic level. This dissertation focuses on bringing about this characterization by cloning the HCoV-NL63 Nucleocapsid gene to be expressed in a bacterial system and transfecting the Nucleocapsid, Membrane and Envelope genes into a Mammalian cell culture system in order for its respective proteins to be expressed. With the use of Bioinformatic analytic tools certain characteristics of HCoV-NL63 Nucleocapsid, Membrane and Envelope proteins are able to be identified, as well as certain motifs and/or regions that are important in the functioning of these proteins. By comparing the results obtained for HCoV-NL63 N,M and E to other well studied coronavirus homologous will enlighten us on the potential role(s) of these proteins in determining HCoV-NL63 pathogenicity and infectivity. vi Although certain functions of these proteins can be deduced by the means of bioinformatics analysis, it is still imperative for it to be extensively characterized In Vitro. This will therefore form a fundamental step in the development of many other projects, which unfortunately fall outside the scope of this M.Sc thesis.

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