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The determination of dioxin-like POPs in sediments and fish of the Vaal Triangle region, Gauteng, South Africa / Claudine NieuwoudtNieuwoudt, Claudine January 2006 (has links)
Water resources in South Africa are scarce, and should therefore be protected against
pollutants, also from persistent organic pollutants (POPs). This is emphasised by the
Stockholm Convention on POPs, which aims at reducing and ultimately eliminating POPs.
South Africa signed and ratified the treaty, and it became international law on 17 May
2004.
POPS are highly stable, toxic, hydrophobic and lipophilic compounds, with the ability to
accumulate in biological tissues. Previous research had shown that dioxin-like POPS are
present in the aquatic environments of South Africa, with the highest concentrations of
these substances measured in industrialised areas of South Africa. The present study
aimed at investigating the extent of polychlorinated dibenzo-para-dioxin (PCDD),
polychlorinated dibenzo-furan (PCDF) and polychlorinated biphenyl (PCB) pollution in the
Vaal Triangle, by targeting aquatic sediments and biota.
Sediment samples were collected from the Blesbok Spruit, Taaibos Spruit, Leeu Spruit and
Suikerbosrand River, and fish tissue samples were collected from Blesbok Spruit and
Suikerbosrand River, to determine bio-accumulation. The samples were extracted with
organic solvents, cleaned-up and fractionated. Raw extracts and fractions were analysed
with the H4IIE-luc reporter gene bio-assay. This bio-assay is a rapid, sensitive and
relatively cost-effective method, which measures the effects of dioxin-like compounds on
rat hepatoma cells, transfected with firefly luciferase gene. Selected samples were
analysed with gas chromatographylmass spectrometry (GCIMS) to confirm results.
Only one site had quantifiable amounts of dioxin-like substances in the sediment,
measured to be 52.35 ng/kg [Effective Concentration 50 (EC 50)]. This value exceeds
many of the European and USA quality guidelines, proposed for sediments. No dioxin-like
substances were found in fish tissues. The absence of PCDD/Fs and PCBs in aquatic
sediments and fish tissues from the Vaal Triangle area might be due to the climatic
conditions of the area, dilution effects in streams, and degradation of these compounds by
UV-radiation and microbial organisms. / Thesis (M. Environmental Science (Water Science))--North-West University, Potchefstroom Campus, 2007.
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The determination of dioxin-like POPs in sediments and fish of the Vaal Triangle region, Gauteng, South Africa / Claudine NieuwoudtNieuwoudt, Claudine January 2006 (has links)
Water resources in South Africa are scarce, and should therefore be protected against
pollutants, also from persistent organic pollutants (POPs). This is emphasised by the
Stockholm Convention on POPs, which aims at reducing and ultimately eliminating POPs.
South Africa signed and ratified the treaty, and it became international law on 17 May
2004.
POPS are highly stable, toxic, hydrophobic and lipophilic compounds, with the ability to
accumulate in biological tissues. Previous research had shown that dioxin-like POPS are
present in the aquatic environments of South Africa, with the highest concentrations of
these substances measured in industrialised areas of South Africa. The present study
aimed at investigating the extent of polychlorinated dibenzo-para-dioxin (PCDD),
polychlorinated dibenzo-furan (PCDF) and polychlorinated biphenyl (PCB) pollution in the
Vaal Triangle, by targeting aquatic sediments and biota.
Sediment samples were collected from the Blesbok Spruit, Taaibos Spruit, Leeu Spruit and
Suikerbosrand River, and fish tissue samples were collected from Blesbok Spruit and
Suikerbosrand River, to determine bio-accumulation. The samples were extracted with
organic solvents, cleaned-up and fractionated. Raw extracts and fractions were analysed
with the H4IIE-luc reporter gene bio-assay. This bio-assay is a rapid, sensitive and
relatively cost-effective method, which measures the effects of dioxin-like compounds on
rat hepatoma cells, transfected with firefly luciferase gene. Selected samples were
analysed with gas chromatographylmass spectrometry (GCIMS) to confirm results.
Only one site had quantifiable amounts of dioxin-like substances in the sediment,
measured to be 52.35 ng/kg [Effective Concentration 50 (EC 50)]. This value exceeds
many of the European and USA quality guidelines, proposed for sediments. No dioxin-like
substances were found in fish tissues. The absence of PCDD/Fs and PCBs in aquatic
sediments and fish tissues from the Vaal Triangle area might be due to the climatic
conditions of the area, dilution effects in streams, and degradation of these compounds by
UV-radiation and microbial organisms. / Thesis (M. Environmental Science (Water Science))--North-West University, Potchefstroom Campus, 2007.
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Construção e manipulação de clone infeccioso de uma amostra brasileira do vírus da diarreia viral bovina / Construction and manipulation of infectious clone from a brazilian bovine viral diarrhea virus isolateArenhart, Sandra 29 March 2012 (has links)
Conselho Nacional de Desenvolvimento Científico e Tecnológico / Bovine viral diarrhea virus (BVDV) is a worldwide pathogen associated with
important losses to livestock production. Most of these losses come from reproductive
disorders and from the ability of the virus to produce persistent infections following in utero
infection of the fetus. A number of reverse genetics methodologies have been used for BVDV
in order to better understand the biology of the virus, which allowed the elucidation of a
number of biological features including virus replication, host-virus interaction, immune
response, and the pathogenesis of fetal infection. The present study describes the construction,
characterization and manipulation of an infectious clone out of a non-cytophatic Brazilian
BVDV strain IBSP4-ncp. The cDNA recombinant clone was constructed by yeast
homologous recombination with a low-copy vector, from three genomic fragments
comprising the open reading frame (ORF). The two untranslated regions (5' and 3' UTR) were
replaced by the respective UTRs of the reference strain NADL. The constructed vector was
transcribed in vitro and the resulting RNA was transfected on MDBK cells to rescue
infectious virus. The rescued viruses (IC-pBSC_IBSP4-ncp#2 and #3) were maintained for
ten passages in tissue culture and characterized in vitro, showing replication dynamics, focus
size and morphology similar to those of the parental IBSP-4. Genomic analysis revealed five
point mutations in the gene coding for Npro protein, resulting in amino acid changes. These
mutations probably reflect an adaptation of the virus to the heterologous UTRs. The infectious
clone IC-pBSC_IBSP4-ncp#2 was further used for the construction of a recombinant virus
expressing the Gaussia luciferase (Gluc) reporter gene. The reporter gene was inserted
between the Npro and Core genes, being flanked by an upstream linker and a downstream
sequence of the Foot and Mouth Disease virus protease (FMDV2Apro) for accurate protein
processing. The recombinant vector was in vitro transcribed and the RNA was transfected on
MDBK cells. Recombinant infectious viruses were rescued (IC-pBSC_IBSP4-ncpGluc#3 and
#4) and characterized in vitro, showing replication dynamics, focus size and morphology
similar to those of the parental IBSP-4 clone. The Gluc reporter gene was accurately
expressed and processed by the recombinant virus during 15 passages in tissue culture. These
studies revealed that the infectious clone constructed herein can be easily manipulated and is
able to carry in its genome heterologous genes up to 555 base pairs in length in a stable
fashion and without interference with its replication efficiency. Thus, the constructed clone
may be very useful for genetic manipulation towards studying different aspects of the BVDV
biology and its interactions with the host, and for the development of vaccine strains with
attenuated phenotype and/or with antigenic markers. / O vírus da diarreia viral bovina (BVDV) é um patógeno de bovinos distribuído
mundialmente, associado com importantes perdas econômicas. As maiores perdas devem-se
aos problemas reprodutivos causados pela infecção, e pela capacidade do vírus de causar
persistência após infecção fetal no terço inicial da gestação. Para entender melhor a biologia
desse vírus, sistemas de genética reversa foram desenvolvidos e tem permitido a elucidação
de vários aspectos da replicação viral, interação vírus hospedeiro, resposta imune e
patogenia da infecção fetal. O presente estudo relata a construção, caracterização e
manipulação de um clone infeccioso, a partir da cepa brasileira não-citopática IBSP4-ncp. O
clone de DNA recombinante foi construído pela técnica de recombinação homóloga em
levedura, utilizando um vetor de baixo número de cópias, construído a partir de três
fragmentos genômicos, que compreendiam a fase aberta de leitura (open reading frame, ORF)
do vírus. As duas regiões não traduzidas (5 e 3 UTR) foram substituídas pelas respectivas
UTRs da cepa de referência NADL. O vetor construído foi transcrito in vitro e o RNA obtido
foi transfectado em células MDBK para recuperação de vírus infecciosos. Os vírus
recuperados (CI-pBSC_IBSP4-ncp#2 e #3) foram mantidos por 10 passagens em cultivo
celular e caracterizados in vitro, apresentando dinâmica de replicação, tamanho e morfologia
de focos similares ao vírus parental IBSP-4. A análise do genoma por sequenciamento revelou
cinco mutações pontuais no gene Npro, com trocas de aminoácidos, provavelmente refletindo
uma adaptação do vírus às UTRs heterólogas. O clone infeccioso construído CIpBSC_
IBSP4-ncp#2, foi então utilizado para a construção de um vírus recombinante
expressando o gene repórter Gaussia luciferase (Gluc). O gene repórter foi inserido entre os
genes Npro e Core do vírus. Para o processamento da proteína repórter, uma sequência ligante
foi adicionada anteriormente ao gene, e a sequência da protease do vírus da Febre Aftosa
(FMDV2Apro) foi inserida após o gene. O vetor recombinante construído foi transcrito in vitro
e o RNA obtido foi transfectado em células MDBK. Vírus recombinantes infecciosos foram
recuperados (CI-pBSC_IBSP4-ncpGluc#3 e #4) e caracterizados in vitro, apresentando
dinâmica de replicação, tamanho e morfologia de focos similares ao vírus obtido do clone
infecioso. O gene repórter Gluc foi corretamente expresso e processado pelo vírus
recombinante durante 15 passagens em cultivo celular. Com os resultados obtidos nestes
estudos, conclui-se que o clone infeccioso construído pode ser facilmente manipulado e é
capaz de carrear em seu genoma, e expressar de forma estável, genes heterólogos com até 555
pares de base, que parecem não interferir com sua capacidade replicativa. Dessa forma, o
clone obtido pode ser muito útil para manipulação genética visando estudar diferentes
aspectos da biologia do BVDV e de suas interações com o hospedeiro, assim como para a
produção de cepas vacinais com fenótipo atenuado e/ou com marcadores antigênicos.
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Using effect-based methods to evaluate the presence of bioactive compounds in food contact materials made of paper and cardboardWänn, Mimmi January 2021 (has links)
Food contact materials are materials that are intended to come into contact with food, and we are exposed to different types of chemicals that exist in the packages on a daily basis. In this study, a battery of effect‑based in vitro cellular bioassays was used to evaluate the presence of bioactive compounds in commonly used food contact materials made of paper and cardboard, retrieved from the Swedish market. Sample extracts were tested at concentrations 0.3, 1, 3 and 10 mg food contact material/mL cell culture medium. The use of effect-based bioassays allowed for screening of multiple health-relevant endpoints in a non-targeted approach. Hence, taking unknown substances and mixtures into consideration when addressing potential toxicity of the materials. In essence, detection of bioactivity could be considered as moderate to high in assays of positive effects. Antiandrogenic and antiestrogenic effects were found in 72% of the samples, followed by 47% bioactivity in the Nrf2 assay. No androgenic effect was detected. Usage of effect-based bioassays allows for high sensitivity and low detection limits, and these can be used as a first approach to evaluate package materials to ensure the safety of consumers. / Livsmedelsförpackningar är material som är avsedda att komma i kontakt med livsmedel. Vi exponeras för olika typer av kemikalier som existerar i dessa förpackningar varje dag. I denna studie användes ett batteri av effektbaserade in vitro bioanalytiska metoder för att undersöka förekomst av bioaktiva ämnen i vanligen använda livsmedelsförpackningar tillverkade av papper och kartong, insamlade från den svenska marknaden. Provextrakten testades i koncentrationerna 0.3, 1, 3 och 10 mg livsmedelsförpackning/mL cellmedium. Att använda effektbaserade bioanalyser möjliggör undersökning av flertalet hälsorelevanta effekter genom en icke-riktad strategi. På så sätt tas okända substanser och komplexa blandningar i beaktande. Andelen bioaktiva prover kan anses måttlig till hög för positiva analyser. Antiandrogena och antiöstrogena effekter detekterades i 72% av proverna, följt av 47% bioaktivitet i Nrf2 analysen. Ingen agonistisk androgen effekt observerades. Att använda effektbaserade bioanalyser möjliggör hög sensitivitet och detektion vid låga koncentrationer, därför kan dessa användas som ett första steg för att evaluera förpackningsmaterial för att säkra konsumenternas hälsa.
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Regulation of Cholesteryl Ester Transfer Protein and Expression of Transporters in the Blood Brain BarrierSuhy, Adam 21 May 2015 (has links)
No description available.
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Molecular biology and biochemistry of regulation of Hrp/type III secretion genes in the corn pathogen Pantoea stewartii pv. stewartiiMerighi, Massimo 27 April 2004 (has links)
No description available.
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Aufbau eines Reportergenassays zur Untersuchung der Wechselwirkung endokriner Disruptoren mit der T 3-regulierten TransaktivierungHofmann, Peter Josef 27 August 2008 (has links)
Das Schilddrüsenhormon Triiodthyronin (T3) ist ein essenzieller Regulator physiologischer Prozesse der Entwicklung, des Wachstums und im Intermediärstoffwechsel. Täglich werden zahlreiche natürliche und synthetische Stoffe aufgenommen, die mit dem endokrinen System interferieren und deshalb als Endokrine Disruptoren (ED) bezeichnet werden. Zur Untersuchung einer direkten Interferenz von ED mit den Schilddrüsenhormonrezeptoren (TR) und ihrer transkriptionellen Aktivität wurde im Rahmen dieser Arbeit ein neues Luziferase-basiertes T3 Reportergensystem mit TRalpha1-transfizierten humanen Leberzellen aufgebaut. Durch Validierung mit dem synthetischen TR-Agonisten GC-1 und dem Antagonisten NH-3 konnte nachgewiesen werden, dass dieser Assay ein hoch-sensitives System zur Analyse von agonistischen sowie antagonistischen Effekten von Testsubtanzen darstellt. Zur Bestimmung der endokrinen Aktivitäten einiger humanrelevanter Vertreter aus den Stoffkategorien der Nahrungsmittel, Kosmetika, Pestizide und Industriechemikalien wurden Dosis-Wirkungskurven in Aktivierungs- und T3-Kompetitionsexperimenten ermittelt. In mikromolaren Konzentrationen wirkten von insgesamt 21 Testsubstanzen einige als reine Agonisten oder Antagonisten während andere gemischt agonistische/antagonistische Effekte hatten. Aufgrund ihrer hier beobachteten Effekte und der gegebenen Humanexposition wird eine eingehendere Analyse von 4-Methylbenzyliden Campher, 4-Nonylphenol, Acetochlor, Benzophenon 2, Benzophenon 3, Bisphenol A, Genistein, Octylmethoxycinnamat, Tetrabromobisphenol A und Xanthohumol empfohlen. Außerdem erwiesen sich einige Metaboliten von Schilddrüsenhormonen als potente Agonisten im T3-Reportergenassay und bedürfen weiterer Aufmerksamkeit. Für die molekulare Charakterisierung der Einflüsse solcher Substanzen auf die T3-regulierte Transaktivierung konnte mit dem hier etablierten Bioassay ein zuverlässiges neues Testsystem für reproduzierbare Screeningserien geschaffen werden. / Triiodothyronine (T3) is a crucial regulator of many physiological processes during development, growth and metabolism. A variety of natural and synthetic substances, which are collectively termed endocrine disrupters (ED) due to their interference with the endocrine system, is taken up on a daily base. A novel luciferase-based T3-responsive reporter gene system employing a human liver cell line transfected with thyroid hormone receptor (TR) alpha1 was established in this work to elucidate the potential molecular interference of certain ED with TR and their transcriptional activity. This assay was validated to be a highly sensitive and reliable tool for analyzing agonistic and antagonistic effects of test compounds using the synthetic TR agonist GC-1 and the antagonist NH-3. Dose-response data of test compounds contained in food, cosmetics, pesticides, plasticizers and other industrial chemicals were obtained after applying the substances alone in activation assays or in combination with T3 in competition assays. In total 21 test compounds were screened of which some acted as pure agonists or antagonists while others were mixed agonists/antagonists in the micromolar concentration range and only one was without effect. Follow-up studies are recommended for some of these substances with regard to their effects as determined in this bioassay and in light of information known on human exposure, i.e., 4-methylbenzyliden camphor, 4-nonylphenol, acetochlor, benzophenone 2, benzophenone 3, bisphenol A, genistein, octylmethoxycinnamate, tetrabromobisphenol A and xanthohumol. In addition some endogenous metabolites of thyroid hormones were surprisingly potent agonists in the T3 reporter gene assay and merit further attention. The novel bioassay established here represents a reliable tool for the screening and molecular characterization of substances interfering with T3-mediated transactivation of gene expression.
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Desenvolvimento de biossensores raciométricos bioluminescentes de pH e metais divalentes baseados na engenharia da região sensível ao pH nas luciferases de vagalumes / Developing of bioluminescent ratiometric biosensors for pH and divalent metals based on the engineering of the pH-sensing moiety of firefly luciferasesGabriel, Gabriele Verônica de Mello 01 December 2017 (has links)
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Abraços
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Previous issue date: 2017-12-01 / Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES) / Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP) / Bioluminescence, the emission of visible light by living organisms is widely used in biosensors. Firefly luciferases and genes are among the most used reporter gene in bioluminescent biosensors. Firefly luciferases are pH-sensitive, exhibiting a red shifted bioluminescence spectra on the presence of metals, high temperatures and acidic pH, being this last property considered unusual for the most analytical applications. Nowadays most luminescent biosensors to metals and pH are fluorescent, and few of them are ratiometric based on spectral changes. Bioluminescent biosensors despite been less common, have same advantages as low background and does not need UV light irradiation, bring no photodamage to the cell. The aim of this project was: (I) study the applicability of the use of Macrolampis sp2 firefly luciferase and other pH-sensitive luciferases as spectral intracellular ratiometric pH biosensor; (II) apply these pH ratiometric biosensors in mammalian cells to investigate its physiology in real time and (III) developing, by engineering the pH sensor region of Macrolampis sp2 firefly luciferase, a ratiometric biosensor specific to metals. We obtained a relation between the pH and the ratio of the bioluminescence at green and red region of the spectra, allowing estimate ratiometrically the intracellular pH of bacteria and mammalian cells. Besides that, we confirmed its use to cellular image of pH and observed that occurs an alkalinization of the cytosol and nucleus during cell division and apoptosis. We demonstrate the applicability of firefly luciferases, in special the luciferase of Macrolampis sp2, as a ratiometric biosensor to metals and intracellular pH. The existence of a linear relationship between the concentrations of metals like cadmium, mercury and zinc, and the ratio of the bioluminescence at green and red region of the spectra, allowed also estimate ratiometrically, for the first time, concentrations of metals less than 100 µM, enabling the use of firefly luciferases as bioavailability indicator to toxic and potential toxic metals. / Bioluminescência, a emissão de luz fria e visível por organismos vivos é amplamente utilizada em biossensores. Luciferases de vagalumes e seus genes estão entre os genes repórteres mais utilizados em biossensores bioluminescentes. Luciferases de vagalumes são sensíveis ao pH, apresentando um deslocamento do espectro de bioluminescência para o vermelho na presença de metais, em temperaturas elevadas e pH ácido, sendo esta última propriedade considerada sem utilidade para a maioria das aplicações analíticas. Atualmente a maioria dos biossensores luminescentes para metais e pH são fluorescentes, poucos deles são raciométricos baseados nas mudanças espectrais. Biossensores bioluminescentes apesar de serem menos comuns, possuem algumas vantagens como baixo background e não necessitam de irradiação com luz UV, não causando fotodanos às células. Os objetivos desse projeto foram: (I) investigar a aplicabilidade de uso da luciferase do vagalume Macrolampis sp2 e outras luciferases pH-sensitivas como biossensor espectral raciométrico intracelular de pH; (II) aplicar esses biossensores raciométricos de pH em células de mamíferos para investigar sua fisiologia em tempo real e (III) desenvolver, por engenharia da região sensora de pH da luciferase de Macrolampis sp2, um biossensor raciométrico específico para metais. Obtivemos uma relação entre o pH e a razão da bioluminescência nas regiões do verde e do vermelho do espectro, permitindo estimar raciometricamente o pH intracelular de bactérias e células de mamíferos. Além disso, confirmamos seu uso para imagem celular de pH, e observamos que ocorre uma alcalinização do citosol e núcleo durante os processos de divisão celular e apoptose. Demonstramos a aplicabilidade das luciferases de vagalumes, em especial a luciferase de Macrolampis sp2, como biossensor raciométrico para metais e pH intracelular. A existência de uma relação linear entre a concentração de metais como cádmio, mercúrio e zinco, e a razão da bioluminescência nas regiões do verde e do vermelho do espectro, permitiu também estimar raciometricamente pela primeira vez concentrações de metais menores que 100 µM, possibilitando o uso de luciferase de vagalumes como indicador de biodisponibilidade de metais tóxicos e potencialmente tóxicos. / FAPESP: 2014/04477-9 / FAPESP: 2015/22603-4 / FAPESP: 2016/15946-5
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Engineered Tracking and Delivery of Mesenchymal Stem Cells (MSCs)Lin, Paul 08 March 2013 (has links)
No description available.
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Kallikrein Gene Regulation in Hormone-Dependent Cancer Cell LinesMyers, Stephen Anthony January 2003 (has links)
Hormone-dependent cancers (HDCs), such as those of the prostate, ovary, breast and endometrium, share characteristics that indicate similar underlying mechanisms of carcinogenesis. Through steroid hormone signalling on "down-stream" target genes, the growth, development and progression of HDCs are regulated. One such family of target genes, highly expressed in HDCs and regulated by steroid hormones, are the tissue kallikreins (KLKs). The KLKs are a multigene family of serine proteases involved in physiological processes such as blood pressure regulation, inflammation, and tumour development and progression via the hydrolysis of specific substrates. Although the KLK gene family is clearly implicated in tumourigenesis, the precise roles played by these genes are largely unknown. Additionally, except for the androgen-responsive genes, KLK2 and KLK3, the mechanisms underlying their hormonal regulation in HDCs are yet to be identified. The initial focus of this thesis was to examine the regulation of the kallikreins, KLK1 and KLK4, by estradiol and progesterone in endometrial and breast cancer cell lines. From these studies, progesterone clearly regulated KLK4 expression in T47D cells and therefore, the focus of the remaining studies was to further examine this regulation at the transcriptional level. An overview of the results obtained is detailed below. Human K1 and hK4 protein levels were increased by 10 nmol/L estradiol benzoate, progesterone, or a combination of the two, over 48 hours in the endometrial cancer cell line, KLE. However, these same treatments resulted in no change in KLK1 gene or hK1 protein levels in the endometrial cancer cell lines, HEC1A or HEC1B (only hK1 analysed). Progesterone treatment (0-100 nmol/L) over 24 hours resulted in a clear increase in KLK4 mRNA at the 10 nmol/L dose in the breast cancer cell line, T47D. Additionally, treatment of T47D cells with 10 nmol/L progesterone over 0-48 hr, resulted in the rapid expression of the hK4 protein at 2 hr which was sustained for 24 hr. Further analysis of this latter progesterone regulation with the antiprogesterone, RU486, over 24 hours, resulted in an observable decrease in hK4 levels at 1 µmol/L RU486. Although the estrogen and progesterone regulation of the hK1 protein was not further analysed, the data obtained for hK4 regulation in T47D cell lines, supported the premise that this gene was progesterone-responsive. The rapid expression of hK4 protein by progesterone at two hours suggests that KLK4 transcription is directly coupled to progesterone regulation, perhaps through progesterone receptor (PR) binding to progesterone-responsive regions within the KLK4 promoter or far "up-stream" regions. Thus, the following further studies were performed. To test this hypothesis, the transcription initiation site (TIS) and 5' flanking regions of the KLK4 gene in T47D cells were interrogated. Primer extension and 5' RACE identified the TIS 78 bp 5' of the putative ATG site for translation as identified by Korkmaz et al. (2001). This KLK4 gene transcript consists of only four exons, and thus excludes the pre/pro signal peptide. Although a TATA-box is not present within -25 to -30 bp 5' of the identified TIS, a number of consensus binding motifs for Sp1 and estrogen receptor half-sites were identified. It is possible that the Sp1 sites are involved in the basal levels of transcription for this gene. Additionally, a putative progesterone response element (PRE) was identified in the far "up-stream" regions of the KLK4 gene. Basal levels of transcription were observed within the KLK4 proximal promoter region when coupled to a luciferase reporter gene and transfected into T47D cell lines. Additionally, the KLK4 proximal promoter region did not induce the luciferase reporter gene expression when progesterone was added to the system, however, estradiol was inhibitory for luciferase gene expression. This suggests that the proximal promoter region of the KLK4 gene could contain functional EREs but not PREs. In keeping with this hypothesis, some ER half-sites were identified, but PR sites were not obvious within this region. The identified PRE in the far "up-stream" region of the KLK4 gene assembled the progesterone receptor in vitro, and in vivo, as assessed by electromobility shift assays and chromatin immunoprecipitation assays (EMSAs and ChIPs), respectively. The binding of the PR to the KLK4 PRE was successfully competed out by a PR antibody and not by an androgen receptor antibody, and thus confirms the specificity of the KLK4 PRE-PR complex. Additionally, the PR was recruited and assembled onto and off the progesterone-responsive KLK4 region in a cyclic fashion. Thus, these data strongly suggest that the PR represents one of the core components of a transcription complex for the KLK4 gene, and presumably also contributes to the expression of this gene. Moreover, these data suggest a functional coordination between the PR and the KLK4 progesterone-responsive region in T47D cells, and thus, provide a model system to further study these events in vivo.
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