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Analise do cDNA e dedução da estrutura primaria de uma PLA2 basica, neurotoxica in vitro, do complexo crotoxina, a partir de mRNA extraido do veneno total de Crotalus durissus collilineatus / Analysis of the cDNA and deduction of the primary structure of a basic, neurotoxic PLA2 in vitro, of the crotoxina complex, from mRNA extracted of the whole venom of Crotalus durissus collilineatusFagundes, Fábio Henrique Ramos 07 December 2005 (has links)
Orientador: Sergio Marangoni / Tese (mestrado) - Universidade Estadual de Campinas / Made available in DSpace on 2018-08-04T18:57:24Z (GMT). No. of bitstreams: 1
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Previous issue date: 2005 / Resumo: Enquanto estudos estruturais de toxinas de veneno de serpentes são feitos usando amostras de veneno, a construção de cDNAs precursores destas toxinas requer o sacrifício do espécime para a extração da glândula de veneno. No presente trabalho nós descrevemos uma técnica simples para isolar mRNAs presentes em amostras de veneno total. Para ilustrar esta técnica nós amplificamos através de RT-PCR um cDNA que codifica uma PLA2 049 (F6) do complexo crotoxina neurotóxica "in vitro" a partir do veneno total da sub espécie Crotalus durissus collilineatus. Estes achados implicam que a aparente ausência do mRNA em matrizes biológicas complexas não são sempre reais e facilitam a maneira de aquisição acelerada de dados micro evolutivos assim como de estrutura-função desta família de proteínas para serem utilizadas como ferramentas moleculares, sem o sacrifício do animal.
O cONA que codifica PLA2 F6 do complexo crotoxina presente no veneno total da sub espécie Crotalus durissus collilineatus foi seqüenciada. A seqüência deduzida de aminoácidos deste cDNA codifica a PLA2 (F6) com alto grau de homologia seqüencial desta família de proteínas PLA2 do grupo 11, incluindo os 14 resíduos de cisteina capazes de dar forma a sete ligações dissulfeto que caracterizam este grupo de PLA2. A PLA2, foi isolada a partir do veneno total da sub espécie Crotalus durissus collilineatus através de coluna de cromatografia convencional de baixa pressão (8ephades G75) e por HPLC fase reversa. A massa molecular foi estimada por espectrometria de massa por MALDI - TOF. Para a identificação desta PLA2 (F6) como uma neurotoxina "in vitro", nós usamos a preparação biventer cervicis de pintainho. A análise filogenética da PLA2 (F6) da sub espécie Crotalus durissus collilineatus mostrou que os subtipos estruturais de N6-PLA2s com a substituição F24 ou 824 evoluíram paralelamente, possivelmente descendendo respectivamente das Protobothrops e a Gloydius dos dias de hoje / Abstract: While structural studies of snake venom toxins can be achieved using venom samples, until now the construction of precursor cDNAs required sacrifice of the specimen for dissection of the venom glands. Here we describe a simple and rapid technique that isolation mRNAs present in whole venom samples. To iIIustrate the technique we have RT-PCR amplified the cDNA that it codifies a "in vitro" neurotoxic protein PLA2 049 (F6) from crotoxin complex, from the venom of snake sub specie, Crotalus durissus collilineatus. These findings imply that the apparent absence of mRNA in complex biological matrices is not always real and paves the way for accelerated acquisition of micro evolution as well as of structure-function of this protein family being used as molecular tools, without sacrifice of animal. The cDNA encoding PLA2 F6 from crotoxin complex in the whole venom of sub specie Crotalus durissus collilineatus venom was sequenced. The deduced amino acid sequence of this cDNA encoded PLA2 (F6) with high overall sequence identity of this protein family to the group 11 PLA2, including the 14 cysteine residues capable of forming seven disulphide bonds that characterize this group of PLA2 enzymes. The PLA2, were isolated from the whole venom of sub specie Crotalus durissus collilineatus by the conventional and low pressure chromatography (8ephades G75) column and the reverse phase HPLC. The molecular mass estimated by MALDI-TOF mass spectrometry. For the identified this PLA2 F6 like as a "in vitro" neurotoxin, we use the neuromuscular blocking activities were assayed with the chick biventer cervicis neuromuscular tissue.
The sub specie' s Crotalus durissus collilineatus PLA2 (F6) phylogeny analysis showed that two structural subtypes of N6-PLA2s with either F24 or 824 substitution have been evolved in parallel, possibly descended respectively from species related to present-day Protobothrops and Gloydius / Mestrado / Bioquimica / Mestre em Biologia Funcional e Molecular
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"Aspectos bioquímicos e moleculares da resistência sistêmica adquirida em cafeeiro contra Hemileia vastatrix" / Biochemical and molecular aspects of systemic acquired resistance in coffee plants against Hemileia vastatrixGuzzo, Sylvia Dias 07 July 2004 (has links)
Com o propósito de contribuir para o esclarecimento dos mecanismos bioquímicos e moleculares envolvidos na resistência sistêmica adquirida (SAR) em plantas suscetíveis contra fitopatógenos, foram conduzidos estudos na interação Coffea arabica-Hemileia vastatrix. A indução de atividade de quitinases e b-1,3-glucanases e o envolvimento dessas enzimas na resistência sistêmica adquirida contra H. vastatrix foram avaliados em cafeeiro suscetível cultivar Mundo Novo (MN) após o tratamento com acibenzolar-S-metil (ASM) (200 mg de i.a./mL). O produto induziu aumento local e sistêmico das atividades de quitinases e b-1,3-glucanases nos tecidos foliares, a partir do primeiro e segundo dia da aplicação do indutor, respectivamente. As atividades enzimáticas atingiram níveis máximos de aumento nas plantas tratadas em relação ao controle, sete dias após a aplicação do ASM. Resistências local e sistêmica ao patógeno foram induzidas a partir do primeiro dia após o tratamento com ASM. A proteção e atividades enzimáticas foram detectadas até 35 dias, após aplicação do indutor. A indução de resistência local contra a ferrugem atingiu um nível máximo de 87% entre 7 e 14 dias. Níveis máximos de proteção sistêmica de 53 a 68% foram observados entre 2 e 21 dias após o tratamento de cafeeiro com o indutor. Neste intervalo de tempo foi observado, também, um aumento sistêmico máximo de atividade enzimática. Os resultados sugerem que o aumento de atividade dessas hidrolases está relacionado com a resistência local e sistêmica, induzida por ASM, em cafeeiro MN contra a ferrugem. Genes relacionados à SAR foram identificados em cafeeiro através de hibridização subtrativa por supressão (HSS), a partir de mRNAs isolados de plantas suscetíveis cv. MN, 72 h após o tratamento com ASM (200 mg i.a./mL). Os mecanismos de respostas de defesa associados à SAR ativada em MN foram comparados, através do isolamento de genes por HSS, com a resistência raça-cultivar específica observada no cafeeiro resistente Híbrido de Timor (HT), 72 h após a inoculação com H. vastatrix. Através da HSS, produziram-se duas bibliotecas de cDNAs subtraídas, enriquecidas de fragmentos de genes induzidos em MN pelo ASM (MN-ASM) ou ativados em HT pelo patógeno (HT-Hv). Os genes encontrados estão envolvidos em diversos processos relacionados à resistência contra fitopatógenos como: formação de espécies de oxigênio reativas, resposta de hipersensibilidade, morte celular programada, síntese e transporte de metabólitos antimicrobianos, percepção e transdução de sinal, síntese de proteínas relacionadas à patogênese, metabolismo de lipídeos e degradação controlada de proteínas. Foi identificado em HT-Hv um número maior de genes implicados em mecanismos de defesa (22%), do que em MN-ASM (16%). Na interação HT-Hv foi detectado um número maior de genes implicados na percepção e transdução de sinal (44%), do que em MN-ASM (30%). Entretanto, o número de genes codificadores de proteínas antimicrobianas foi maior no MN com resistência induzida (22%), do que no cafeeiro resistente HT inoculado com o patógeno (6%). Foram isolados de HT-Hv e MN-ASM, genes codificadores de b-1,3-glucanases e as seqüências completas puderam ser determinadas através da técnica RACE. Os resultados obtidos sugerem que a resistência em HT-Hv e MN-ASM ocorre através de mecanismos distintos. / Studies on the interaction Coffea arabica-Hemileia vastatrix were performed in order to contribute to the elucidation of biochemical and molecular mechanisms involved in systemic acquired resistance (SAR) developed in susceptible plants against pathogens. Induction of chitinase and b-1,3-glucanase activities and their involvement in systemic acquired resistance against H. vastatrix were evaluated in susceptible coffee plants cultivar "Mundo Novo" (MN) after treatment with acibenzolar-S-methyl (ASM) (200 mg a.i./mL). The product induced local and systemic increases in chitinase and b-1,3-glucanase activities in leaf tissues, starting from the first and second days after inducer application, respectively. The increases in enzymatic activity reached their maximum levels in treated plants compared to control seven days after application of ASM. Induction of local and systemic resistance against pathogen was detected one day after ASM treatment. Protection and increases in enzyme activities were detected up to 35 days after product application. Induction of local resistance against coffee leaf rust reached a highest level of 87% between 7 and 14 days. Highest levels of systemic protection ranging from 53% to 68% were observed in coffee plants between 2 and 21 days after inducer treatment. During the same time frame maximum increases in systemic enzymatic activity were also observed. Results suggest that the increases in these hydrolase activities were correlated with the local and systemic resistance induced by ASM in coffee plants against coffee leaf rust. Genes related to SAR were identified in coffee plants by suppression subtractive hybridization (SSH), from mRNA isolated from susceptible plants cv. MN 72 h after treatment with ASM (200 mg a.i./mL). The mechanisms of defense responses associated with SAR activated in MN were compared through the isolation of genes by SSH, with the race-specific resistance observed in the resistant coffee plant "Híbrido de Timor" (HT) 72 h after the inoculation with H. vastatrix. By SSH technique two subtracted cDNA libraries were constructed enriched for gene fragments induced in MN by ASM (MN-ASM) or activated in HT by pathogen infection (HT-Hv). The isolated genes were involved in different processes related to resistance against pathogens, such as: production of active oxygen species, hypersensitive response, programmed cell death, synthesis and transport of antimicrobial metabolites, signal perception and transduction, synthesis of pathogenesis-related proteins, lipid metabolism and selective degradation of proteins. It was identified in HT-Hv a higher number of defense-related genes (22 %) than in MN-ASM (16 %). The incompatible interaction HT-Hv showed a higher number of genes implicated in the signal perception and transduction (44 %) than MN-ASM (30 %). However, the number of genes encoding antimicrobial proteins was higher in the susceptible cultivar MN with induced resistance (22 %) than in the resistant coffee plant HT inoculated with the incompatible pathogen (6 %). Genes encoding b-1,3-glucanases were isolated from HT-Hv and MN-ASM and their complete sequences could be obtained by RACE procedure. Results suggest that distinct recognition events and defense pathways are involved in the expression of resistance in HT-Hv and MN-ASM.
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"Aspectos bioquímicos e moleculares da resistência sistêmica adquirida em cafeeiro contra Hemileia vastatrix" / Biochemical and molecular aspects of systemic acquired resistance in coffee plants against Hemileia vastatrixSylvia Dias Guzzo 07 July 2004 (has links)
Com o propósito de contribuir para o esclarecimento dos mecanismos bioquímicos e moleculares envolvidos na resistência sistêmica adquirida (SAR) em plantas suscetíveis contra fitopatógenos, foram conduzidos estudos na interação Coffea arabica-Hemileia vastatrix. A indução de atividade de quitinases e b-1,3-glucanases e o envolvimento dessas enzimas na resistência sistêmica adquirida contra H. vastatrix foram avaliados em cafeeiro suscetível cultivar Mundo Novo (MN) após o tratamento com acibenzolar-S-metil (ASM) (200 mg de i.a./mL). O produto induziu aumento local e sistêmico das atividades de quitinases e b-1,3-glucanases nos tecidos foliares, a partir do primeiro e segundo dia da aplicação do indutor, respectivamente. As atividades enzimáticas atingiram níveis máximos de aumento nas plantas tratadas em relação ao controle, sete dias após a aplicação do ASM. Resistências local e sistêmica ao patógeno foram induzidas a partir do primeiro dia após o tratamento com ASM. A proteção e atividades enzimáticas foram detectadas até 35 dias, após aplicação do indutor. A indução de resistência local contra a ferrugem atingiu um nível máximo de 87% entre 7 e 14 dias. Níveis máximos de proteção sistêmica de 53 a 68% foram observados entre 2 e 21 dias após o tratamento de cafeeiro com o indutor. Neste intervalo de tempo foi observado, também, um aumento sistêmico máximo de atividade enzimática. Os resultados sugerem que o aumento de atividade dessas hidrolases está relacionado com a resistência local e sistêmica, induzida por ASM, em cafeeiro MN contra a ferrugem. Genes relacionados à SAR foram identificados em cafeeiro através de hibridização subtrativa por supressão (HSS), a partir de mRNAs isolados de plantas suscetíveis cv. MN, 72 h após o tratamento com ASM (200 mg i.a./mL). Os mecanismos de respostas de defesa associados à SAR ativada em MN foram comparados, através do isolamento de genes por HSS, com a resistência raça-cultivar específica observada no cafeeiro resistente Híbrido de Timor (HT), 72 h após a inoculação com H. vastatrix. Através da HSS, produziram-se duas bibliotecas de cDNAs subtraídas, enriquecidas de fragmentos de genes induzidos em MN pelo ASM (MN-ASM) ou ativados em HT pelo patógeno (HT-Hv). Os genes encontrados estão envolvidos em diversos processos relacionados à resistência contra fitopatógenos como: formação de espécies de oxigênio reativas, resposta de hipersensibilidade, morte celular programada, síntese e transporte de metabólitos antimicrobianos, percepção e transdução de sinal, síntese de proteínas relacionadas à patogênese, metabolismo de lipídeos e degradação controlada de proteínas. Foi identificado em HT-Hv um número maior de genes implicados em mecanismos de defesa (22%), do que em MN-ASM (16%). Na interação HT-Hv foi detectado um número maior de genes implicados na percepção e transdução de sinal (44%), do que em MN-ASM (30%). Entretanto, o número de genes codificadores de proteínas antimicrobianas foi maior no MN com resistência induzida (22%), do que no cafeeiro resistente HT inoculado com o patógeno (6%). Foram isolados de HT-Hv e MN-ASM, genes codificadores de b-1,3-glucanases e as seqüências completas puderam ser determinadas através da técnica RACE. Os resultados obtidos sugerem que a resistência em HT-Hv e MN-ASM ocorre através de mecanismos distintos. / Studies on the interaction Coffea arabica-Hemileia vastatrix were performed in order to contribute to the elucidation of biochemical and molecular mechanisms involved in systemic acquired resistance (SAR) developed in susceptible plants against pathogens. Induction of chitinase and b-1,3-glucanase activities and their involvement in systemic acquired resistance against H. vastatrix were evaluated in susceptible coffee plants cultivar "Mundo Novo" (MN) after treatment with acibenzolar-S-methyl (ASM) (200 mg a.i./mL). The product induced local and systemic increases in chitinase and b-1,3-glucanase activities in leaf tissues, starting from the first and second days after inducer application, respectively. The increases in enzymatic activity reached their maximum levels in treated plants compared to control seven days after application of ASM. Induction of local and systemic resistance against pathogen was detected one day after ASM treatment. Protection and increases in enzyme activities were detected up to 35 days after product application. Induction of local resistance against coffee leaf rust reached a highest level of 87% between 7 and 14 days. Highest levels of systemic protection ranging from 53% to 68% were observed in coffee plants between 2 and 21 days after inducer treatment. During the same time frame maximum increases in systemic enzymatic activity were also observed. Results suggest that the increases in these hydrolase activities were correlated with the local and systemic resistance induced by ASM in coffee plants against coffee leaf rust. Genes related to SAR were identified in coffee plants by suppression subtractive hybridization (SSH), from mRNA isolated from susceptible plants cv. MN 72 h after treatment with ASM (200 mg a.i./mL). The mechanisms of defense responses associated with SAR activated in MN were compared through the isolation of genes by SSH, with the race-specific resistance observed in the resistant coffee plant "Híbrido de Timor" (HT) 72 h after the inoculation with H. vastatrix. By SSH technique two subtracted cDNA libraries were constructed enriched for gene fragments induced in MN by ASM (MN-ASM) or activated in HT by pathogen infection (HT-Hv). The isolated genes were involved in different processes related to resistance against pathogens, such as: production of active oxygen species, hypersensitive response, programmed cell death, synthesis and transport of antimicrobial metabolites, signal perception and transduction, synthesis of pathogenesis-related proteins, lipid metabolism and selective degradation of proteins. It was identified in HT-Hv a higher number of defense-related genes (22 %) than in MN-ASM (16 %). The incompatible interaction HT-Hv showed a higher number of genes implicated in the signal perception and transduction (44 %) than MN-ASM (30 %). However, the number of genes encoding antimicrobial proteins was higher in the susceptible cultivar MN with induced resistance (22 %) than in the resistant coffee plant HT inoculated with the incompatible pathogen (6 %). Genes encoding b-1,3-glucanases were isolated from HT-Hv and MN-ASM and their complete sequences could be obtained by RACE procedure. Results suggest that distinct recognition events and defense pathways are involved in the expression of resistance in HT-Hv and MN-ASM.
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Genomic Analysis of Nematode-Environment InteractionAdhikari, Bishwo 15 July 2010 (has links) (PDF)
The natural environments of organisms present a multitude of biotic and abiotic challenges that require both short-term ecological and long-term evolutionary responses. Though most environmental response studies have focused on effects at the ecosystem, community and organismal levels, the ultimate controls of these responses are located in the genome of the organism. Soil nematodes are highly responsive to, and display a wide variety of responses to changing environmental conditions, making them ideal models for the study of organismal interactions with their environment. In an attempt to examine responses to environmental stress (desiccation and freezing), genomic level analyses of gene expression during anhydrobiosis of the Antarctic nematode Plectus murrayi was undertaken. An EST library representative of the desiccation induced transcripts was established and the transcripts differentially expressed during desiccation stress were identified. The expressed genome of P. murrayi showed that desiccation survival in nematodes involves differential expression of a suite of genes from diverse functional areas, and constitutive expression of a number of stress related genes. My study also revealed that exposure to slow desiccation and freezing plays an important role in the transcription of stress related genes, improves desiccation and freezing survival of nematodes. Deterioration of traits essential for biological control has been recognized in diverse biological control agents including insect pathogenic nematodes. I studied the genetic mechanisms behind such deterioration using expression profiling. My results showed that trait deterioration of insect pathogenic nematode induces substantial overall changes in the nematode transcriptome and exhibits a general pattern of metabolic shift causing massive changes in metabolic and other processes. Finally, through field observations and molecular laboratory experiments the validity of the growth rate hypothesis in natural populations of Antarctic nematodes was tested. My results indicated that elemental stoichiometry influences evolutionary adaptations in gene expression and genome evolution. My study, in addition to providing immediate insight into the mechanisms by which multicellular animals respond to their environment, is transformative in its potential to inform other fundamental ecological and evolutionary questions, such as the evolution of life-history patterns and the relationship between community structure and ecological function in ecosystems.
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IL-17A induced response and synergy with otherproinflammatory cytokines in human endothelial cellsSalin, Julia January 2021 (has links)
Cardiovascular diseases are a broad group of diseases, such as heart attack and heart failureaffecting the cardiovascular system. The primary cause of cardiovascular diseases isatherosclerosis, and its progression is brought about by oxidative stress and a complex chronicinflammation reaction cascade. Of central importance are proinflammatory cytokines, regulatedby multiple factors, including interleukin (IL) 17A. This project aims to investigate the effectof IL-17A on the inflammatory response of human vascular endothelial cells by quantifyingchemokine C-X-C motif ligand-1 (CXCL1) release when exposed or not to otherproinflammatory mediators such as TNF-𝛼, IL-6 and IL-1β. To investigate this, humanumbilical cord endothelial cells were cultured and then stimulated with IL-17A alone or incombination with other cytokines, namely IL-6/sIL6R, IL-1β, or TNF-𝛼. After an appropriateincubation time following the stimulations, the supernatants of the cells were collected, and theamount of CXCL1 was analysed with ELISA or qPCR, respectively. At a lower concentration(10ng/ml), IL-17A failed to induce a significant level of CXCL1 release from endothelial cells.However, IL-17A + TNF-𝛼 (5ng/ml) greatly enhanced, higher than inductions from individualtreatments combined, level of CXCL1 release from endothelial cells. Furthermore, combiningIL-17A with IL-1β or IL-6 induced non-abundant and abundant upregulation in CXCL1 release,respectively. On transcription level, the amount of CXCL1 mRNA induced by IL-17A alonewas non-significant, but stimulation with TNF-𝛼 and IL-17A + TNF-𝛼 induced significantlyupregulated expression of CXCL1. In conclusion, we found that IL-17A induced synergeticrelease of CXCL1 in human vascular endothelial cells with TNF-𝛼. In addition, the synergisticimpact of IL-17A and TNF-𝛼 in terms of CXCL1 induction in vascular endothelial cells wasevident on a transcriptional level. Our data imply that combined blockage of IL-17A and TNF-𝛼 could have an enhanced therapeutic effect on vascular inflammation.
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