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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.
51

Functional studies on the nuclear receptor Nurr1 /

Nordzell, Mariette, January 2004 (has links)
Diss. (sammanfattning) Stockholm : Karol inst., 2004. / Härtill 4 uppsatser.
52

Studies on the nuclear receptor Nurr1 : identification of Nurr1-regulated genes /

Hermanson, Elisabet, January 2004 (has links)
Diss. (sammanfattning) Stockholm : Karol inst., 2004. / Härtill 5 uppsatser.
53

Loss of IkB[alpha]-mediated regulation correlates with increased oncogenicity of mutant c-Rel proteins

Leanna, Candice A. January 1998 (has links)
Thesis (Ph. D.)--University of Missouri--Columbia, 1998. / Typescript. Vita. Includes bibliographical references (leaves : 172-189). Also available on the Internet.
54

Molecular characterization of transcription factor GABP redox regulation, promoter structure, and mechanisms of assembly /

Chinenov, Yurii January 1999 (has links)
Thesis (Ph. D.)--University of Missouri--Columbia, 1999. / Typescript. Vita. Includes bibliographical references (leaves 137-154). Also available on the Internet.
55

Functional characterization of the liver-enriched transcription factorCREB-H

Chin, King-tung, Tony., 錢景彤. January 2005 (has links)
published_or_final_version / abstract / Biochemistry / Doctoral / Doctor of Philosophy
56

Determination of phosphorylation sites of Drosophila melanogaster exuperantia protein by site-directed mutagenesis.

January 1999 (has links)
Chan Kam Leung. / Thesis (M.Phil.)--Chinese University of Hong Kong, 1999. / Includes bibliographical references (leaves 175-182). / Abstract also in Chinese. / Acknowledgements --- p.i / Abstract --- p.ii / Abbreviations --- p.v / Table of Contents --- p.vii / Chapter Chapter 1 --- General Introduction / Chapter 1.1 --- Drosophila as a model for studying development --- p.1 / Chapter 1.2 --- The formation of the body axis in Drosophila --- p.2 / Chapter 1.3 --- The maternal genes are essential for development --- p.9 / Chapter 1.4 --- Maternal gene bicoid is essential for formation of the anterior structures in the embryo --- p.11 / Chapter 1.5 --- The formation of the biocid protein gradient from anterior pole to posterior pole of the embryo --- p.13 / Chapter 1.6 --- The bed protein gradient controls the downstream zygotic target genes in a concentration-dependent manner --- p.15 / Chapter 1.7 --- The formation of the bed protein gradient in embryo --- p.17 / Chapter 1.8 --- Components required for bcd mRNA localization at anterior pole of oocyte --- p.21 / Chapter 1.8.1 --- Cis-acting elements --- p.21 / Chapter 1.8.2 --- Trans-acting elements --- p.21 / Chapter 1.9 --- The properties of exuperantia protein --- p.25 / Chapter 1.9.1 --- The function of exu protein --- p.25 / Chapter 1.9.2 --- Exuperantia is a phosphoprotein --- p.26 / Chapter 1.9.3 --- Phosphorylation pattern of exuperantia protein is stage-specific --- p.28 / Chapter 1.9.4 --- Reversible phosphorylation is one of the major mechanisms to control protein activity in all eukaryotic cells --- p.29 / Chapter 1.9.5 --- The relationship between the exu protein phosphorylation and the bcd mRNA localization --- p.30 / Chapter 1.10 --- Aim of project --- p.31 / Chapter CHAPTER 2 --- Preparation of the exuperantia genomic DNA and complement DNA (cDNA) mutant Constructs / Chapter 2.1 --- Introduction --- p.33 / Chapter 2.2 --- Materials and methods --- p.35 / Chapter 2.2.1 --- DNA preparation methods --- p.35 / Chapter 2.2.1.1 --- Preparation of double-stranded DNA by polyethylene glycol6000 --- p.35 / Chapter 2.2.1.2 --- Preparation of M13mp8 single-stranded DNA --- p.37 / Chapter 2.2.1.3 --- "Preparation of double-stranded DNA by Biol prep (Modified from Maniatis et al.,1989)" --- p.38 / Chapter 2.2.2 --- "Preparation of DH5α,JM109, TG1 competent cells" --- p.39 / Chapter 2.2.3 --- Bacteria transformation --- p.40 / Chapter 2.2.4 --- Restriction enzyme digestion --- p.40 / Chapter 2.2.5 --- Phenol/chloroform extraction --- p.41 / Chapter 2.2.6 --- Purification of DNA fragment by electro-elution --- p.42 / Chapter 2.2.7 --- DNA ligation --- p.43 / Chapter 2.2.8 --- DNA dephosphorylation --- p.43 / Chapter 2.2.9 --- In vitro site-directed mutagenesis --- p.44 / Chapter 2.2.9.1 --- The Sculptor´ёØ in vitro mutagenesis --- p.44 / Chapter 2.2.9.2 --- The GeneEditor´ёØ in vitro site-directed mutagenesis --- p.47 / Chapter 2.2.10 --- The double-stranded or single-stranded DNA sequencing by T7 DNA polymerase sequencing system --- p.50 / Chapter 2.2.11 --- Denatured polyacrylamide gel electorphoresis --- p.51 / Chapter 2.2.11 --- Nucleotide sequence of the sequencing primers and the mutageneic oligonucleotides --- p.54 / Chapter 2.3 --- Results --- p.55 / Chapter 2.3.1 --- Design exuperantia mutant constructs --- p.55 / Chapter 2.3.1.1 --- Comparison of exu protein amino acids sequence with different Drosophila species --- p.56 / Chapter 2.3.2 --- The exu genomic mutant constructs --- p.63 / Chapter 2.3.3 --- The exu cDNA mutant constructs --- p.63 / Chapter 2.4 --- Discussion --- p.76 / Chapter CHAPTER 3 --- Epitope tagging of exuperantia protein with c-myc eptiope / Chapter 3.1 --- Introduction --- p.79 / Chapter 3.2 --- Materials and methods --- p.84 / Chapter 3.2.1 --- Preparation of the c-myc eptiope DNA fragment --- p.84 / Chapter 3.2.2 --- End-filling of 5'overhang DNA fragment by Klenow fragment --- p.86 / Chapter 3.2.3 --- In vitro translation of protein by TNT® Quick coupled transcription and translation system --- p.86 / Chapter 3.2.4 --- Immunoprecipitation of recombinant exu protein --- p.87 / Chapter 3.2.5 --- Sodium Dodecyl Sulfate-Polyacrylamide Gel Electrophoresis (SDS-PAGE) --- p.88 / Chapter 3.2.5.1 --- SDS-PAGE preparation --- p.88 / Chapter 3.2.5.2 --- SDS-PAGE electrophoresis --- p.90 / Chapter 3.2.6 --- Western blot analysis --- p.90 / Chapter 3.2.6.1 --- Transfer the protein to a nitro-cellulose membrane by semi-dried blotting --- p.90 / Chapter 3.2.6.2 --- Western blot blocking and antibody recognition --- p.91 / Chapter 3.3 --- Results --- p.92 / Chapter 3.3.1 --- Construction of the plasmid containing exu cDNA tagging with a c-myc epitope --- p.92 / Chapter 3.3.2 --- In vitro translation of c-myc epitope tagged exu protein --- p.102 / Chapter 3.3.3 --- Immunoprecipitation of c-myc labeled exu protein by a polyclonal rabbit anti-exu antibody and monoclonal mouse anti-myc antibody --- p.104 / Chapter 3.4 --- Discussion --- p.109 / Chapter CHAPTER 4 --- In vitro phosphorylation of exuperantia Protein / Chapter 4.1 --- Introduction --- p.111 / Chapter 4.2 --- Materials and methods --- p.113 / Chapter 4.2.1 --- Exogenous kinase phsophorylation reactions --- p.113 / Chapter 4.2.2 --- Separation of the phosphorylated exu protein variants by SDS- PAGE --- p.114 / Chapter 4.3 --- Results --- p.115 / Chapter 4.3.1 --- Western blot analysis of in vitro translated exu protein variants --- p.115 / Chapter 4.3.2 --- Phosphorylation of in vitro translated exu protein variants by exogenous cAMP-dependent protein kinase --- p.118 / Chapter 4.3.3 --- Phosphorylation of in vitro translated exu protein variants by exogenous cGMP-dependent protein kinase --- p.123 / Chapter 4.3.4 --- Phosphorylation of in vitro translated exu protein variants by exogenous protein kinase C --- p.128 / Chapter 4.4 --- Discussion --- p.133 / Chapter CHAPTER 5 --- Introduction of the exuperantia genomic constrcuts into the germline of Drosophila by P element-mediated transformation / Chapter 5.1 --- Introduction --- p.136 / Chapter 5.2 --- Materials and methods --- p.138 / Chapter 5.2.1 --- Construction of a genomic construct for production of transgenic flies --- p.138 / Chapter 5.2.2 --- Preparation of double-stranded DNA by ultra-centrifugation --- p.142 / Chapter 5.2.3 --- P-element mediated transformation --- p.143 / Chapter 5.2.3.1 --- Eggs collection --- p.143 / Chapter 5.2.3.2 --- Dechorionating the eggs --- p.143 / Chapter 5.2.3.3 --- Orientating the eggs --- p.144 / Chapter 5.2.3.4 --- Microinjection --- p.145 / Chapter 5.2.4 --- Collecting virgin female Drosophila --- p.146 / Chapter 5.2.5 --- Setup a crossing experiment --- p.146 / Chapter 5.2.6 --- Preparation of total ovaries and testes extracts exu protein from Female and male Drosophila --- p.147 / Chapter 5.2.7 --- Immunohistochemical distribution of exuperantia protein --- p.147 / Chapter 5.3 --- Results --- p.150 / Chapter 5.3.1 --- Insertion of the mutated exu fragments into the Drosophila Transformation vector (pCaSpeR) --- p.150 / Chapter 5.3.2 --- Introduction of the mutated exu gene into the genome of Drosophila by P-element mediated transformation --- p.153 / Chapter 5.3.3 --- Western blot analysis of the exu protein in the exu (ES2.1) transgenic fly --- p.160 / Chapter 5.3.4 --- Immunohistochemical distribution of exu protein in exuES21 mutants --- p.162 / Chapter 5.3.5 --- Rescue test of exuES2.1 trangenic flies --- p.165 / Chapter 5.4 --- Discussion --- p.168 / Chapter CHAPTER 6 --- General Discussion --- p.171 / References --- p.173 / Chapter Appendix I: --- List of reagents --- p.183 / Chapter Appendix II: --- Publication --- p.187
57

Replication Protein A in the Maintenance of Genome Stability

Deng, Sarah January 2015 (has links)
High fidelity double strand break repair is paramount for the maintenance of genome integrity and faithful passage of genetic information to the following generation. Homologous recombination (HR) and non-homologous end joining (C-NHEJ) have evolved as the two major pathways for the efficient and accurate repair of double strand breaks (DSBs). In addition, a minor Ku- and Ligase IV-independent end-joining pathway has been identified and implicated in the formation of chromosomal translocations. This alternative end-joining pathway occurs by bridging the break ends through annealing between short microhomologies, hence the name microhomology-mediated end joining (MMEJ). In addition to these defined DSB repair pathways, a broken DNA end possesses immense mutagenic potential to generate chromosomal rearrangements. Diverse and complex rearrangements are a commonly observed feature amongst cancer cells. The focus of this thesis is to examine the role of Replication Protein A (RPA) in binding single-stranded DNA (ssDNA) repair intermediates to promote error free repair and to prevent mutagenic chromosomal deletions and rearrangements. RPA is a highly conserved, heterotrimeric ssDNA binding protein with a ubiquitous role in all DNA transactions involving ssDNA intermediates. RPA promotes resection at DSBs to facilitate HR and abrogation of this function has severe consequences. Defective RPA can lead to the formation of secondary structures and impair loading of homology search proteins such as Rad52 and Rad51. Using a chromosomal end-joining assay, we demonstrate that hypomorphic rfa1 mutants exhibit elevated frequencies of MMEJ by up to 350-fold. Biochemical characterization of RPAt33 and RPAt48 complexes show these mutants are compromised for their ability to prevent spontaneous annealing and the removal of secondary structures to fully extend ssDNA. These results demonstrate that annealing between MHs defines a critical control to regulate MMEJ repair. Therefore, RPA bound to ssDNA intermediates shields complementary sequences from annealing to promote error-free HR and prevents repair by mutagenic MMEJ, thereby preserving genomic integrity. RPA also impedes intrastrand annealing between short inverted repeat sequences to prevent the formation of foldback structures. Foldbacks have been proposed to drive palindromic gene amplification, a genome destabilizing rearrangement that can disrupt the protein expression equilibrium and is a prevalent phenomenon within tumor cells. Palindromic duplications are elevated ~1000-fold in rfa1-t33 sae2Δ and rfa1-t33 mre11-H125N mutants compared to sae2Δ or mre11-H125N, yet we did not detect these events in the hypomorphic rfa1-t33 mutant. This suggests that Mre11 and Sae2 play critical roles in preventing palindromic amplification through regulation of the Mre11 structure-specific endonuclease to process DNA foldbacks (also called DNA hairpins). Therefore, Mre11-Sae2 together with RPA prevent palindromic gene amplification. Together, these data focus the spotlight on RPA playing active central and supporting roles to sustain genome stability. This additionally raises that notion that secondary structures are potent instigators and mediators of many genome rearrangements and their prevention by RPA is absolutely crucial.
58

Expression and functional study of foxp4 in the central nervous system of zebrafish.

January 2012 (has links)
Forkhead domain基因家族編碼了很多對於胚胎發育至關重要的轉錄因子,而Foxp4則屬於p-subtype forkhead轉錄因子其中一員。Foxp4在胚胎發育期間的表達十分活躍,在發育中的腦部的不同地方表達,但其於中樞神經系統發育中的調控角色並不清楚。Foxp4基因剔除小鼠在出生前死於心臟的缺陷表型(心二分支) ,在此時間段,腦部的發育才剛剛開始,因此我們無法利用Foxp4基因剔除小鼠作為研究中樞神經系統發育的動物模型。最近,我們的團隊利用小腦組織培養技術及siRNA發佈的研究顯示,Foxp4在小鼠小腦中的蒲金氏細胞(Purkinje cell)中擔當著重要的維持作用。這項研究結果加深了我們對研究Foxp4在中樞神經系統發育中的調控角色的決心。 / 本論文旨在利用斑馬魚作為實驗模型,研究foxp4在斑馬魚中樞神經系統發育中的表達及調控角色。RT-PCR結果顯示foxp4在斑馬魚發育中的bud stage開始表達,並在及後的階段維持其表達水平。利用原位雜交技術 (whole mount in-situ hybridization),我們發現foxp4表達的地區主要集中於發育中的腦部。在成年斑馬魚中,foxp4表達在不同組織和器官,包括腦部,眼睛和心臟。成年斑馬魚腦部切片原位雜交 (sectioned in-situ hybridization)則顯示,foxp4在小腦的蒲金氏細胞和視頂蓋(optic tectum)的periventricular gray zone表達。 / 為了進一步探究foxp4對於胚胎發育過程中的功能,我們利用微注射技術,把反義嗎啉 (morpholino) MO1注射到斑馬魚胚胎中,大幅度抑制foxp4的表達水平。胚胎受精後48小時,MO1注入的胚胎顯示出第四腦室腦積水的缺陷表型。組織學分析顯示,第四腦室以下的延髓被壓縮致形態異常。此外,利用原位雜交技術及不同的分子標記,我們發現胚胎的中後腦邊界也會出現輕度畸形,而後腦的神經元數量及排列亦受到影響。 / 本項研究展示foxp4在胚胎中樞神經系統的發展的重要性,亦提供了新的見解。我們認為foxp4可能是調控腦室發育的重要成員,但在此方面與foxp4相關的分子機制仍須作更深入的研究。 / The forkhead domain gene family encodes a large group of transcription factors that play essential roles in development. Foxp4 is one of the members in the Foxp subfamily that expressed in different parts of developing central nervous system (CNS) and its function is less characterized. Previous study on Foxp4-knockout mice resulted in early embryonic lethality due to defective heart tube development that hindered the functional study of Foxp4 in CNS development. Recently, our laboratory reported that Foxp4 functions as a maintenance role in the Purkinje cell in the mouse cerebellum. Nevertheless, the role of foxp4 in CNS development was still unclear. / In this study, we used zebrafish as a model to study the expression pattern and functional study of foxp4 in the developing CNS. RT-PCR analysis showed that foxp4 transcript was expressed at the bud stage and maintained in the later embryonic stages. Whole-mount in-situ hybridization showed that foxp4 expressed in the cephalic region during embryonic development. In adult zebrafish, foxp4 expresses in different tissues and organs including brain, eye and heart. Sectioned in-situ hybridization of the adult zebrafish brain showed that foxp4 was specifically expressed in the Purkinje cell and the periventricular gray zone of optic tectum. / To further investigate the function of foxp4 during embryonic development, we injected antisense morpholino, MO1 into the zebrafish embryo to knockdown foxp4. By 48 hour post fertilization (hpf), MO1-injected embryos displayed hydrocephalus in the 4th ventricle. Histological analysis revealed that the medulla oblongata below the 4th ventricle was compressed by the edema resulting in abnormal morphology of medulla oblongata in the MO1-injected morphant. In addition, a mild malformation of the mid-hindbrain boundary, disrupted hindbrain patterning was observed in MO1-injected morphant. / Our findings provide new insight into the function of foxp4 in embryonic CNS development. We suggested that foxp4 may be essential in regulating the brain ventricle development while the molecular mechanism underlying the functional role of foxp4 requires further investigation. / Detailed summary in vernacular field only. / Detailed summary in vernacular field only. / Detailed summary in vernacular field only. / Detailed summary in vernacular field only. / Wong, Wai Kei. / Thesis (M.Phil.)--Chinese University of Hong Kong, 2012. / Includes bibliographical references (leaves 92-102). / Abstracts also in Chinese. / Abstract --- p.iii / 摘要 --- p.v / Acknowledgement --- p.vii / Figure and table list --- p.xi / Abbreviation --- p.xii / Chapter Chapter 1 --- General Introduction / Chapter 1.1 --- Zebrafish as a developmental model --- p.1 / Chapter 1.2 --- Zebrafish development with highlights --- p.3 / Chapter 1.2.1 --- CNS development --- p.3 / Chapter 1.3 --- Forkhead domain gene in development --- p.5 / Chapter 1.3.1 --- History of forkhead domain gene --- p.5 / Chapter 1.3.2 --- Functional roles of forkhead domain genes in development --- p.6 / Chapter 1.4 --- Foxp subfamily --- p.8 / Chapter 1.4.1 --- Diverse functions of Foxp1, 2, 3 and 4 --- p.8 / Chapter 1.4.2 --- Relationship between Foxp subfamily members --- p.10 / Chapter 1.5 --- Foxp4 --- p.11 / Chapter 1.5.1 --- Genomic organization and protein structure of mFoxp4 --- p.11 / Chapter 1.5.2 --- Previous studies of mFoxp4 --- p.14 / Chapter 1.5.3 --- Foxp4 studies in other model organisms --- p.14 / Chapter 1.5.3.1 --- Rat --- p.15 / Chapter 1.5.3.2 --- Xenopus --- p.16 / Chapter 1.5.3.3 --- C. elegans --- p.16 / Chapter 1.5.4 --- Zebrafish foxp4 --- p.17 / Chapter 1.5.5.1 --- Genomic organization and protein structure of foxp4 --- p.17 / Chapter 1.5.5.2 --- Sequence alignment of foxp4 with other models --- p.19 / Chapter 1.6 --- Hypothesis, aim and strategy of the study --- p.22 / Chapter Chapter 2 --- Expression of foxp4 in zebrafish embryo and adult zebrafish brain / Chapter 2.1 --- Introduction --- p.24 / Chapter 2.2 --- Materials and methods --- p.25 / Chapter 2.2.1 --- Animals --- p.25 / Chapter 2.2.2 --- Materials --- p.26 / Chapter 2.2.3 --- Semi-quantitative PCR --- p.35 / Chapter 2.2.3.1 --- cDNA of zebrafish embryo --- p.35 / Chapter 2.2.3.2 --- Isolation of adult zebrafish organs --- p.36 / Chapter 2.2.3.3 --- RNA extraction and reverse transcription --- p.36 / Chapter 2.2.3.4 --- Polymerase chain reaction --- p.37 / Chapter 2.2.4 --- Subcloning of DNA fragment / Chapter 2.2.4.1 --- Preparation of cloning vectors --- p.40 / Chapter 2.2.4.2 --- Subcloning of DNA fragments --- p.40 / Chapter 2.2.4.3 --- Transformation of DNA into competent cells --- p.40 / Chapter 2.2.4.4 --- Preparation of recombinant plasmid DNA --- p.41 / Chapter 2.2.5 --- Whole mount in-situ hybridization of zebrafish embryo --- p.45 / Chapter 2.2.5.1 --- Preparation of equipment --- p.45 / Chapter 2.2.5.2 --- Preparation of zebrafish embryos --- p.45 / Chapter 2.2.5.3 --- Preparation of RNA probe --- p.46 / Chapter 2.2.5.4 --- Whole-mount in-situ hybridization --- p.48 / Chapter 2.2.6 --- Sectioned in-situ hybridization of adult zebrafish brain --- p.49 / Chapter 2.2.6.1 --- Histology of adult zebrafish brain --- p.49 / Chapter 2.2.6.2 --- Sectioned in-situ hybridization --- p.50 / Chapter 2.3 --- Results --- p.51 / Chapter 2.3.1 --- Expression profile of foxp4 in different stages of zebrafish embryo --- p.51 / Chapter 2.3.2 --- Expression pattern of foxp4 in different stages of zebrafish embryo --- p.54 / Chapter 2.3.3 --- Expression profile of foxp4 in different zebrafish organs and tissues --- p.57 / Chapter 2.3.4 --- Expression pattern of foxp4 in adult zebrafish brain --- p.59 / Chapter 3.4 --- Discussion --- p.61 / Chapter Chapter 3 --- Functional analysis of foxp4 in zebrafish embryonic development / Chapter 3.1 --- Introduction --- p.63 / Chapter 3.2 --- Materials and methods --- p.64 / Chapter 3.2.1 --- Materials --- p.64 / Chapter 3.2.2 --- Design of morpholino --- p.68 / Chapter 3.2.3 --- Sequencing of morpholino target regions of foxp4 --- p.70 / Chapter 3.2.4 --- Microinjection --- p.70 / Chapter 3.2.4.1 --- Preparation of materials and equipment --- p.70 / Chapter 3.2.4.2 --- Preparation of injection needle --- p.70 / Chapter 3.2.4.3 --- Preparation of morpholinos --- p.70 / Chapter 3.2.4.4 --- Calibration of injection volume --- p.71 / Chapter 3.2.4.5 --- Microinjection of zebrafish embryo --- p.71 / Chapter 3.2.5 --- Western blotting to assay foxp4 translation inhibition --- p.72 / Chapter 3.2.5.1 --- Preparation of protein extracts --- p.72 / Chapter 3.2.5.2 --- Coomassie blue staining --- p.73 / Chapter 3.2.5.3 --- Western blotting --- p.74 / Chapter 3.2.6 --- Whole mount in-situ hybridization --- p.74 / Chapter 3.3 --- Results --- p.75 / Chapter 3.3.1 --- MO1 knockdown efficiency assayed by Western blotting --- p.75 / Chapter 3.3.2 --- General morphology of morphants --- p.77 / Chapter 3.3.3 --- Histology at the hindbrain region showing the phenotype --- p.79 / Chapter 3.3.4 --- Whole mount in-situ hybridization of different molecular markers --- p.81 / Chapter 3.4 --- Discussion --- p.85 / Chapter Chapter 4 --- Future directions and conclusion / Chapter 4.1 --- Future directions --- p.89 / Chapter 4.2 --- Conclusion --- p.91 / Reference --- p.92
59

Transcriptional repression by CTIP2, a C₂H₂ zinc finger protein /

Topark-Ngarm, Acharawan Khamsiritrakul. January 1900 (has links)
Thesis (Ph. D.)--Oregon State University, 2007. / Printout. Includes bibliographical references. Also available on the World Wide Web.
60

DNA binding and beyond : an investigation of proteins involved in PAH-induced carcinogesesis

Hooven, Louisa Ada 15 December 2003 (has links)
Exposure to polycyclic aromatic hydrocarbons such as benzo[a]pyrene (B[a]P) has been determined to be a risk factor for various forms of human cancer. PAH DNA adducts have been shown to cause mutations, but carcinogenesis is also accompanied by alterations in gene expression. Inhibiting individual cytochrome P450s could clarify the interaction of P450s and other enzymes in the activation of polycyclic aromatic hydrocarbons to DNA binding intermediates. Phosphorodiamidate morpholino oligomers (PMOs), a class of antisense agents were targeted against cytochrome P450 1A1 (CYP1A1) and cytochrome P450 1B1 (CYP1BI). No significant inhibition of enzyme activity or expression was observed with any PMO used as measured by ethoxyresorufin-O-deethylase (EROD) activity and immunoblots. It was demonstrated that BPDE may react with PMOs in vitro, and PMOs may be segregated in lysosomes, blocking their efficacy. Nonspecific effects by the PMO on CYP1A1 activity were observed. These observations indicate multiple confounding effects in the use of PMOs for this purpose. Many of the genes regulated by histone deacetylases are involved in proliferation, cell function, and differentiation, and HDAC inhibitors are of great interest in cancer research. To probe epigenetic regulation of CYP1A1, MCF-7 cells were treated with two HDAC inhibitors, suberoylanilide hydroxamic acid (SAHA) and trichostatin A (TSA). SARA and TSA increased EROD activity and in RT-PCR. SARA and TSA reduced B[a]P induced CYP1A1 and CYP1B1 mRNA levels. B[a]P DNA binding was not significantly altered by SAHA or TSA treatment. To assay global protein expression changes after treatment with PAR, MCF-7 cells were treated with B[a]P, DB{a,1]P, coal tar extract (SRM 1597) and diesel exhaust extract (SRM 1975), Proteins were separated by two-dimensional electrophoresis, and analyzed using PDQuest. Spots of interest were excised and identified by matrix assisted laser desorption/ionization time of flight time of flight mass spectroscopy. Alterations in expression of heat shock proteins, cytoskeletal proteins, DNA associated proteins, and glycolytic and mitochondrial proteins were observed. Universally increased expression was observed for tubulin alpha and myosin light chain alkali, cyclophilin B, heterogeneous nuclear riboprotein B1, and alpha enolase. Additional proteins exhibiting change in expression included histone H2A.1, heat shock protein 70-2, galectin-3, nucleoside diphosphate kinase, ATP synthase, and electron transfer flavoprotein. / Graduation date: 2004

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