41 |
The Nickel-responsive Binding and Regulation of Two Novel Helicobacter pylori NikR–targeted GenesAdemi, Irsa 11 July 2013 (has links)
Nickel is an essential transition metal for the virulence and survival of Helicobacter pylori in the acidic human stomach. The nickel– and proton– dependent transcriptional regulator HpNikR is important for maintaining nickel homeostasis inside the cytosol by regulating multiple H. pylori genes. A previous ChIP-sequencing experiment with H. pylori G27 and HpNikR identified two novel genes currently annotated as putative iron-transporters, HpG27_866 and HpG27_1499. In vitro DNA-binding assays with the promoter sequences of the two genes revealed nickel-dependent HpNikR binding with an affinity of ~10-7 M. The recognition site of HpNikR was identified on HpG27_1499 by footprinting assays, which loosely correlates with the HpNikR pseudo-consensus sequence. Furthermore, HpG27_1499 transcription showed nickel-dependent repression in WT H. pylori, and no changes in an isogenic ΔnikR strain. These data suggest that HpG27_1499 could be a nickel importer that is regulated by HpNikR in a nickel-responsive manner.
|
42 |
The Nickel-responsive Binding and Regulation of Two Novel Helicobacter pylori NikR–targeted GenesAdemi, Irsa 11 July 2013 (has links)
Nickel is an essential transition metal for the virulence and survival of Helicobacter pylori in the acidic human stomach. The nickel– and proton– dependent transcriptional regulator HpNikR is important for maintaining nickel homeostasis inside the cytosol by regulating multiple H. pylori genes. A previous ChIP-sequencing experiment with H. pylori G27 and HpNikR identified two novel genes currently annotated as putative iron-transporters, HpG27_866 and HpG27_1499. In vitro DNA-binding assays with the promoter sequences of the two genes revealed nickel-dependent HpNikR binding with an affinity of ~10-7 M. The recognition site of HpNikR was identified on HpG27_1499 by footprinting assays, which loosely correlates with the HpNikR pseudo-consensus sequence. Furthermore, HpG27_1499 transcription showed nickel-dependent repression in WT H. pylori, and no changes in an isogenic ΔnikR strain. These data suggest that HpG27_1499 could be a nickel importer that is regulated by HpNikR in a nickel-responsive manner.
|
43 |
Mechanisms of Recombinant Heat Shock Protein 27 Atheroprotection: NF-κB Signaling in MacrophagesSalari, Samira 05 March 2012 (has links)
The O’Brien lab has demonstrated that Heat shock protein 27 (HSP27)shows attenuated expression in human coronary arteries as the degree of atherosclerosis progresses. Moreover, over-expression of HSP27 reduces
atherogenesis in mice. The precise mechanism(s) for HSP27-mediated "atheroprotection" are incompletely understood. Nuclear Factor-kappaB (NF-κB)
is a key signaling modulator in atherogenesis. Hence, this project sought to determine if recombinant HSP27 (rHSP27) alters NF-κB signaling to affect atheroprotection. Treatment of THP1 macrophages with rHSP27 resulted in degradation of IκBα, coincided with nuclear translocation of the p65 subunit and produced transcriptional evidence of activation of NF-κB signaling. When the transcriptional profile of THP1 macrophages treated with rHSP27 was analyzed using NF-κB-pathway-specific qRT-PCR arrays, among the regulated genes, IL-10 and GM-CSF mRNA levels were markedly increased, as were parallel translational effects observed. These data provide new mechanistic insights into the atheroprotective effects of HSP27.
|
44 |
Molecular characterisation of primary wool follicle initiation in Merino sheep.McGrice, Hayley Ann January 2010 (has links)
Primary wool follicles are initiated in the skin of sheep foetuses at approximately day 50 of gestation as the result of complex reciprocal molecular interactions between the mesenchyme and overlying epithelium. The lifetime wool production potential and fibre diameter of the Merino sheep is dependent on the total number of follicles initiated in utero. Understanding the molecular events that surround primary wool follicle initiation may provide approaches to enhance or manipulate this process in order to maximise the profitability of wool production enterprises. In order to study the morphological and molecular changes occurring during early wool follicle development, a foetal skin series spanning primary follicle initiation was generated. Foetal skin was sampled from the shoulder, midside and rump of four foetuses at 8 time points between day 43 and day 68 of gestation. Histological characterisation of the shoulder skin samples revealed that primary epidermal placodes emerged at around day 53, dermal condensates were visible from day 57 and downgrowth of the follicle began at day 68. An equation relating age of the foetus (day of gestation post AI) and crown-rump length, specific to Merino foetuses, was developed for use in future studies of this nature. Molecular markers of fibroblast migration, epidermal and dermal stem cells and cell proliferation were selected to test the hypothesis that dermal condensates are initiated at discrete sites beneath the epidermis as a result of a combination of migration and arrangement of multipotent pre-papilla cells. Quantitative reverse transcription polymerase chain reaction (qRT-PCR) analysis of RAC1 and RHOa (migration markers), β1-integrin and alkaline phosphatase (stem cell markers), proliferative nuclear cell antigen and cyclinB1 (proliferation markers), patched-1, selected tumor necrosis factor (TNF) signalling molecules and eleven reference genes was conducted using midside and rump skin samples from each of four foetuses from the 8 time points. geNorm analysis of the reference and target genes revealed that the migration markers RAC1 and RHOa along with GAPDH were the most stably expressed genes in this sample series. Significant changes in mRNA expression were detected for β1-integrin, alkaline phosphatase, patched-1 and the TNF members EDA, EDAR, TROY and TRAF6. Many of these significant differences in expression coincided with key morphological events. Significant differences in expression were also detected between the midside and rump samples for numerous transcripts. Laser capture microdissection (LCM) was implemented for analysis of the target transcripts within particular structures of foetal sheep skin. Frozen tissue sectioning, staining, LCM, RNA extraction and cDNA synthesis were optimised for qRT-PCR analysis of endogenous controls and selected TNF transcripts. Several RNA extraction methods and reverse transcription approaches were trialled to ensure optimum extraction and reverse transcription efficiency for this tissue type. Exogenous mRNA transcripts were also incorporated prior to RNA extraction and reverse transcription to track reaction efficiency between samples. A comparison of different slide types revealed that laser pressure catapulting from membrane slides was an absolute requirement for foetal skin tissue studies. Follicle regions (including the epidermal placode and dermal condensate) and the adjacent non-follicle regions were laser captured from foetal skin, and the mRNA expression levels of patched-1 and selected TNF members was compared. Preliminary qRT-PCR analysis using this technique revealed that EDAR, TROY and PTCH1 mRNA levels were higher in the follicle regions than the non-follicle regions. The TNF signalling pathway appears to play an important role in primary wool follicle initiation and patterning at different sites on the body. Spatial differences in expression of some of these regulators may be involved in initiating different types of follicles. The molecular events surrounding primary wool follicle initiation also show a high degree of conservation between sheep, humans, and mice. Considering the high degree of DNA sequence conservation as well as the histological, signalling and cycling similarities between sheep and humans, sheep may represent a better model for the study of human hair follicle initiation and disease than the currently used mice and rat models. / http://proxy.library.adelaide.edu.au/login?url= http://library.adelaide.edu.au/cgi-bin/Pwebrecon.cgi?BBID=1523639 / Thesis (Ph.D.) -- University of Adelaide, School of Agriculture, Food and Wine, 2010
|
45 |
Mecanismos de tolerância ao Al3+ em plantas comparando espécie de Cerrado (Styrax camporum), limoeiro ‘cravo’ (Citrus limonia cv. cravo) e trigo (Triticum aestivum) / Al-tolerance mechanisms in plants comparing Cerrado species (Styrax camporum), 'Rangpur' lime (Citrus limonia) and wheat (Triticum aestivum)Silva, Carolina de Marchi Santiago da [UNESP] 28 November 2017 (has links)
Submitted by CAROLINA DE MARCHI SANTIAGO DA SILVA null (carolmsantiago@gmail.com) on 2018-01-26T00:36:21Z
No. of bitstreams: 1
tese_ repositório.pdf: 9864100 bytes, checksum: 750ed24c6bf82e4cb76088a6ef42e3ee (MD5) / Approved for entry into archive by Ana Paula Santulo Custódio de Medeiros null (asantulo@rc.unesp.br) on 2018-01-26T11:13:36Z (GMT) No. of bitstreams: 1
silva_cms_dr_rcla.pdf: 9847207 bytes, checksum: d4dc0d33ef54769d644003d06014b328 (MD5) / Made available in DSpace on 2018-01-26T11:13:36Z (GMT). No. of bitstreams: 1
silva_cms_dr_rcla.pdf: 9847207 bytes, checksum: d4dc0d33ef54769d644003d06014b328 (MD5)
Previous issue date: 2017-11-28 / Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP) / Presente em solos ácidos, o alumínio principalmente encontrado na sua forma tóxica (Al3+) tem como principal efeito a diminuição do crescimento radicular. O Cerrado ocorre no centro-oeste do Brasil sob solos ácidos (pH <4) e com alto teor de alumínio (Al). Citrus limonia cv ‘Cravo’ Osbeck e Styrax camporum Pohl compartilham localização geográfica e características edáficas em que se estabelecem, no entanto exibem respectivamente sensibilidade e tolerância ao Al. O presente trabalho visa elucidar mecanismos envolvidos no estresse por Al3+ a nível de expressão gênica radicular. Para as duas espécies foi feita uma análise de transcriptoma para avaliar os efeitos do Al por uma perspectiva global, e a partir destes resultados alguns genes foram selecionados para avaliação ao longo de experimentos de hidroponia mantido por 60 dias. São discutidas estratégias de tolerância e sensibilidade ao Al nas duas espécies, juntamente com análises de biometria, quantificação hormonal e anatomia que corroboram o comportamento sensível de Citrus e tolerante de Styrax por diversas vias. Além disso, o último capítulo trata da dependência do pH em um importante mecanismo de tolerância ao Al em trigo envolvendo exsudação de ácido orgânico. / Present in acid soils, aluminum mainly found in its toxic form (Al3+) has as main effect the decrease of root growth. Cerrado occurs in central-western Brazil under acid soils (pH <4) and high aluminum content (Al). Citrus limonia (Osbeck) and Styrax camporum (Pohl) share geographic location and edaphic characteristics in where they are settled, however exhibiting respectively Al-sensitivity and Al-tolerance. The present work aims to elucidate the mechanisms involved in Al3+ stress at root gene expression level. For both species, a transcriptome analysis was performed to evaluate the effects of Al in a global perspective, and from these results some genes were selected for evaluation in hydroponic experiments maintained for 60 days. Al tolerance and sensitivity strategies are discussed in both species, together with analyzes of biometrics, hormonal quantification and anatomy data that corroborate the Al-sensitive behavior of Citrus and Al-tolerance in Styrax by several routes. In addition, the last chapter deals with the dependence of pH on one important mechanism of Al tolerance in wheat involving organic acid exudation. / FAPESP: 2013/11370-3
|
46 |
Análise funcional dos genes ASR - Abscisic acid, Stress and Ripening - de arroz (Oryza sativa L.) em resposta ao estresse por alumínioArenhart, Rafael Augusto January 2008 (has links)
Um dos graves obstáculos para a manutenção e estabilidade da produção nacional de arroz (Oryza sativa) reside na susceptibilidade dos genótipos existentes a estresses abióticos. Tendo em vista a importância social e econômica do arroz e os efeitos extremamente danosos desses estresses sobre a agricultura, o conhecimento detalhado das interações entre os estresses abióticos e as respostas dos vegetais frente a esses estímulos ambientais faz-se necessário. O alumínio (Al) é considerado um dos principais fatores limitantes na produção agrícola, inibindo o crescimento das raízes e a absorção de minerais. A toxicidade do Al em plantas ocorre pela sua solubilização em solos com pH baixo ou solos ácidos. Os genes ASR (ABA, Stress and Ripening) são induzidos por estresse e ácido abscísico (ABA) em plantas, e seus níveis de expressão são rapidamente aumentados em resposta à salinidade e seca. Recentemente, foi demonstrado que o gene que codifica a proteína ASR5 é responsivo ao Al em raízes de arroz. Apesar do arroz ser considerado um dos cereais mais resistentes a Al, os mecanismos básicos de tolerância a este metal são pouco conhecidos no arroz em comparação a outros cereais. Por meio do presente trabalho objetivamos: i) a caracterização funcional dos membros da família gênica ASR de arroz em reposta ao Al; e ii) a construção de vetores binários de transformação de plantas visando o estudo da localização subcelular da proteína codificada pelo gene OsASR5, e o silenciamento gênico da família ASR de arroz. As análises dos transcritos por qRT-PCR mostraram que todos os genes da família ASR de arroz ssp Japonica respondem ao Al. Por outro lado, OsASR5 não sofre modulação de sua expressão em resposta ao Al em raízes de arroz ssp Indica. Essas diferenças de respostas dos genes OsASR5 em distintas variedades pode refletir diferenças no grau de tolerância ao Al de cada um desses genótipos. / One of the major obstacles to maintain the stability of the national production of rice (Oryza sativa) lies on the susceptibility of the different genotypes to abiotic stress. In view of the social and economic importance of rice and due to the extremely harmful effects of stress in agriculture, detailed knowledge of the interactions between these stresses and plant responses to environmental stimuli is necessary. Aluminum (Al) is considered one of the main limitation factors for agricultural productivity, inhibiting root growth and mineral absorption. Al toxicity occurs by its solubilization in soils with low pH or acid soils. The ASR (ABA, Stress and Ripening) genes are induced by stress and abscisic acid (ABA) in plants, and their expression levels are quickly increased in response to salinity and drought. Recently, it was demonstrated that the ASR5 gene is responsive to Al in rice roots. Despite the fact that rice is considered one of the most resistant crops to Al, the basic mechanisms of tolerance to this metal are poorly known when compared to other crops. This study aimed the functional characterization of the gene expression of rice ASR family members in response to Al, and the construction of binary vectors for the subcellular localization of the protein codified by the OsASR5 gene, and the construction of a gene silencing binary vector for the ASR family. Analyses of transcripts by qRT-PCR showed that in the ssp Japonica, all ASR genes responded to Al. In contrast, OsASR5 do not suffer expression modulation in response to Al in rice roots of ssp Indica. These differences in response of the OsASR5 gene in distinct varieties may reflect differences in the degree of Al tolerance in each genotype.
|
47 |
Molecular and biochemical characterization of serine protease SmSP1 in \kur{Schistosoma mansoni}OPAVSKÝ, David January 2013 (has links)
SmSP1 is a chimerical serine protease consisted of three domains (cub, LDLa and trypsin-like) and found in Schistosoma mansoni. Its characterization was performed by molecular techniques such as PCR screen, qRT-PCR and RNA interference (RNAi) to gain information about expression profile, level expression and susceptibility to RNAi. Further, protein expression was carried out to gain an antigen for immunization and recombinant for biochemical studies. Results of PCR screen and qRT-PCR suggested possible function of SmSP1 in egg and adult stages but SmSP1 gene was not found susceptible to RNAi in NTS. Recombinant from E. coli was successfully used for immunization. Active recombinant was likely expressed in Pichia pastoris but expression conditions are unstable and expression optimization is necessary.
|
48 |
Antivirotické účinky stilbenoidů proti klíšťaty přenášeným patogenům in vivoMAŠKOVÁ, Hana January 2018 (has links)
This study was focused on antiviral effects of stilbenoids against a virus transmitted by ticks. The cell viability of selected cell line cultures in the presence of various concentrations of stilbenoids was determined using the MTT assay. Similarly, the mixed effect of other known antiviral substances and stilbenoids was studied using the MTT assay. Both the prophylactic effects of stilbenoids on the infected culture cell lines and the effect on viral replication were examined. The viral titres from samples were determined using plaque assay. Some of the experiments were performed also in vivo using laboratory mice.
|
49 |
Análise funcional dos genes ASR - Abscisic acid, Stress and Ripening - de arroz (Oryza sativa L.) em resposta ao estresse por alumínioArenhart, Rafael Augusto January 2008 (has links)
Um dos graves obstáculos para a manutenção e estabilidade da produção nacional de arroz (Oryza sativa) reside na susceptibilidade dos genótipos existentes a estresses abióticos. Tendo em vista a importância social e econômica do arroz e os efeitos extremamente danosos desses estresses sobre a agricultura, o conhecimento detalhado das interações entre os estresses abióticos e as respostas dos vegetais frente a esses estímulos ambientais faz-se necessário. O alumínio (Al) é considerado um dos principais fatores limitantes na produção agrícola, inibindo o crescimento das raízes e a absorção de minerais. A toxicidade do Al em plantas ocorre pela sua solubilização em solos com pH baixo ou solos ácidos. Os genes ASR (ABA, Stress and Ripening) são induzidos por estresse e ácido abscísico (ABA) em plantas, e seus níveis de expressão são rapidamente aumentados em resposta à salinidade e seca. Recentemente, foi demonstrado que o gene que codifica a proteína ASR5 é responsivo ao Al em raízes de arroz. Apesar do arroz ser considerado um dos cereais mais resistentes a Al, os mecanismos básicos de tolerância a este metal são pouco conhecidos no arroz em comparação a outros cereais. Por meio do presente trabalho objetivamos: i) a caracterização funcional dos membros da família gênica ASR de arroz em reposta ao Al; e ii) a construção de vetores binários de transformação de plantas visando o estudo da localização subcelular da proteína codificada pelo gene OsASR5, e o silenciamento gênico da família ASR de arroz. As análises dos transcritos por qRT-PCR mostraram que todos os genes da família ASR de arroz ssp Japonica respondem ao Al. Por outro lado, OsASR5 não sofre modulação de sua expressão em resposta ao Al em raízes de arroz ssp Indica. Essas diferenças de respostas dos genes OsASR5 em distintas variedades pode refletir diferenças no grau de tolerância ao Al de cada um desses genótipos. / One of the major obstacles to maintain the stability of the national production of rice (Oryza sativa) lies on the susceptibility of the different genotypes to abiotic stress. In view of the social and economic importance of rice and due to the extremely harmful effects of stress in agriculture, detailed knowledge of the interactions between these stresses and plant responses to environmental stimuli is necessary. Aluminum (Al) is considered one of the main limitation factors for agricultural productivity, inhibiting root growth and mineral absorption. Al toxicity occurs by its solubilization in soils with low pH or acid soils. The ASR (ABA, Stress and Ripening) genes are induced by stress and abscisic acid (ABA) in plants, and their expression levels are quickly increased in response to salinity and drought. Recently, it was demonstrated that the ASR5 gene is responsive to Al in rice roots. Despite the fact that rice is considered one of the most resistant crops to Al, the basic mechanisms of tolerance to this metal are poorly known when compared to other crops. This study aimed the functional characterization of the gene expression of rice ASR family members in response to Al, and the construction of binary vectors for the subcellular localization of the protein codified by the OsASR5 gene, and the construction of a gene silencing binary vector for the ASR family. Analyses of transcripts by qRT-PCR showed that in the ssp Japonica, all ASR genes responded to Al. In contrast, OsASR5 do not suffer expression modulation in response to Al in rice roots of ssp Indica. These differences in response of the OsASR5 gene in distinct varieties may reflect differences in the degree of Al tolerance in each genotype.
|
50 |
Expressão gênica diferencial e análise protéica do leite de búfalas sadias e com mastite subclínica / Differential gene expression and analysis of milk proteins from dairy buffalo with and without subclinical mastitisTanamati, Fernanda 27 February 2018 (has links)
Submitted by FERNANDA TANAMATI null (fertanamati@gmail.com) on 2018-03-22T00:14:15Z
No. of bitstreams: 1
Tese_Tanamati_versão final.pdf: 1118298 bytes, checksum: ad444e697e657dd704d25b099b8eeede (MD5) / Approved for entry into archive by Alexandra Maria Donadon Lusser Segali null (alexmar@fcav.unesp.br) on 2018-03-22T10:54:04Z (GMT) No. of bitstreams: 1
tanamati_f_dr_jabo.pdf: 1118298 bytes, checksum: ad444e697e657dd704d25b099b8eeede (MD5) / Made available in DSpace on 2018-03-22T10:54:04Z (GMT). No. of bitstreams: 1
tanamati_f_dr_jabo.pdf: 1118298 bytes, checksum: ad444e697e657dd704d25b099b8eeede (MD5)
Previous issue date: 2018-02-27 / Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP) / A mastite em búfalas leiteiras causa perdas econômicas devido à diminuição da produção de leite, além de ter um efeito negativo no bem-estar dos animais. Deste modo, foram realizados dois estudos: o objetivo do estudo I foi avaliar o nível de expressão dos genes da lactoferrina (LTF), fator de necrose tumoral alfa (TNF-α), interleucina-1 beta (IL-1β), interleucina-8 (IL-8), e toll-like receptors 2 (TLR-2) e 4 (TLR-4) em búfalas Murrah com e sem mastite subclínica. Amostras de leite de 12 búfalas com mastite e 12 de búfalas sem mastite foram coletadas, para a extração de RNA, síntese de cDNA e validação dos perfis de expressão por qRT-PCR. O ΔΔCt foi estimado utilizando contrastes ortogonais da expressão dos genes alvo corrigidos para a expressão dos genes housekeeping entre os tratamentos. A expressão dos genes TLR-2, TLR-4, TNF-α, IL-1β e IL-8 foi regulada positivamente em búfalos com mastite, enquanto que o gene LTF não apresentou expressão diferencial. O estudo desses genes da função imune que são ativos na glândula mamária é importante para o desenvolvimento de estratégias destinadas a preservar a saúde do úbere. O objetivo do estudo II foi avaliar as proteínas presentes no soro do leite de búfalas com e sem mastite subclínica, utilizando uma abordagem proteômica para identificar proteínas diferencialmente expressas e potencial biomarcador para a doença. Para isso, 16 amostras de leite de búfalas Murrah foram coletadas, sendo oito animais com e oito animais sem mastite subclínica. O método contagem espectral foi utilizado para quantificar a abundância relativa das proteínas individuais e os bancos de dados de proteínas anotadas para Bubalus bubalis e para Bos taurus foram utilizados na análise. Após integração das anotações genéticas das referências de búfalos e bovinos, foram identificadas 1.033 proteínas, das quais 156 proteínas foram diferencialmente reguladas entre animais sadios e infectados. Foram identificados 18 processos biológicos nos quais essas proteínas participam e a catelicidina-3 foi identificada como um potencial biomarcador da mastite subclínica. Os resultados são importantes para compreender melhor o comportamento da mastite na glândula mamária das búfalas e, portanto, podem auxiliar no diagnóstico precoce da doença. / Mastitis in dairy buffalo causes economic losses due to decreased milk production, along with having a negative effect on the animals’ welfare. Thus, two studies were performed: the objective of study I was to evaluate the expression levels of lactoferrin (LTF), tumor necrosis factor alpha (TNF-α), interleukin-1 beta (IL-1β), interleukin- 8 (IL-8) and toll-like receptors 2 (TLR-2) and 4 (TLR-4) in Murrah buffaloes with and without subclinical mastitis. Milk samples were collected from 12 buffaloes with mastitis and 12 buffaloes without mastitis for RNA extraction, cDNA synthesis, and validation of expression profiles by qRT-PCR. The ΔΔCt was estimated using orthogonal contrasts of the target genes expression adjusted for the expression of the housekeeping genes between both treatments. The expression of the TLR-2, TLR-4, TNF-α, IL-1β and IL-8 genes were upregulated in buffaloes with mastitis, while the LTF gene showed no differential expression. The study of these immune function genes that are active in the mammary gland is important for the development of strategies aimed at preserving the health of the udder. The objective of study II was to evaluate the proteins present in the milk whey from buffaloes with and without subclinical mastitis, using a proteomic approach to identify differentially expressed proteins and potential biomarkers for the disease. For this, 16 samples of Murrah buffalo milk were collected, comprised of eight animals with and eight animals without subclinical mastitis. The spectral counting method was used to quantify the relative abundance of the individual proteins, and the databases of proteins annotated for Bubalus bubalis and for Bos taurus were used in the analysis. After integrating the gene annotations from the buffalo and bovine references, a total of 1,033 proteins were identified, of which 156 proteins were differentially regulated between healthy and affected animals. 18 biological processes in which these proteins participate were identified, and cathelicidin-3 was identified as a potential biomarker of subclinical mastitis. These results are important to better understand the behavior of mastitis in the buffalo mammary gland, and in turn may aid in the early diagnosis. / FAPESP: 14/19321-4 / FAPESP: 14/25309-7 / FAPESP: 16/10526-8
|
Page generated in 0.0287 seconds