In vertebrates, the embryonic hindbrain is transiently subdivided along its anterior-posterior (A-P) axis into 8 well defined segments termed rhombomeres (r1-8). Each rhombomere represents a true cellular compartment in transcriptional profile, lineage restriction and neuronal organization. Thus, the vertebrate hindbrain provides a beautiful model for studying mechanisms of anterior-posterior patterning, signal transduction and interpretation, initiation and maintenance of transcriptional profiles, cell sorting and border formation. The Kreisler/MafB gene, which encodes a basic leucine zipper (bZIP) transcription factor that regulates some Hox genes, is one of the first genes to be expressed segmentally in the hindbrain, and is subject to a dynamic and complex regulatory process. However, unlike the Hox genes, Kreisler/MafB is not located within a large cluster of genes and therefore provides a simple system for dissecting the molecular mechanisms involved in hindbrain compartmentalization. In dissecting the mechanisms that govern Kreisler/MafB regulation, we have identified the S5 regulatory element that directs early MafB expression in the future r5-r6 domain. We have found a binding site within S5 that is specific for the Variant Hepatocyte Nuclear Factor 1 (vHNF1) to be essential, but not sufficient for early induction of r5-r6-specific expression. Thus, early inductive events that initiate MafB expression are clearly distinct from later acting ones that modulate its expression levels. Using mouse mutants, we have shown that MafB is dependent on the M33 polycomb protein and other mechanisms of chromatin remodeling. We then utilized transgenic flies and mice as well as binding assays to identify and validate a PcG/trxG response element (PRE), PRE1 which acts to reorganize the surrounding chromatin, regulating S5-dependent expression. To our knowledge, PRE1 is the first validated vertebrate PcG/trxG response element. Thus, PRE1 provides a springboard for further exploration of the mechanisms governing chromatin remodeling.

In vertebrates, the embryonic hindbrain is transiently subdivided along its anterior-posterior (A-P) axis into 8 well defined segments termed rhombomeres (r1-8). Each rhombomere represents a true cellular compartment in transcriptional profile, lineage restriction and neuronal organization. Thus, the vertebrate hindbrain provides a beautiful model for studying mechanisms of anterior-posterior patterning, signal transduction and interpretation, initiation and maintenance of transcriptional profiles, cell sorting and border formation. The Kreisler/MafB gene, which encodes a basic leucine zipper (bZIP) transcription factor that regulates some Hox genes, is one of the first genes to be expressed segmentally in the hindbrain, and is subject to a dynamic and complex regulatory process. However, unlike the Hox genes, Kreisler/MafB is not located within a large cluster of genes and therefore provides a simple system for dissecting the molecular mechanisms involved in hindbrain compartmentalization. In dissecting the mechanisms that govern Kreisler/MafB regulation, we have identified the S5 regulatory element that directs early MafB expression in the future r5-r6 domain. We have found a binding site within S5 that is specific for the Variant Hepatocyte Nuclear Factor 1 (vHNF1) to be essential, but not sufficient for early induction of r5-r6-specific expression. Thus, early inductive events that initiate MafB expression are clearly distinct from later acting ones that modulate its expression levels. Using mouse mutants, we have shown that MafB is dependent on the M33 polycomb protein and other mechanisms of chromatin remodeling. We then utilized transgenic flies and mice as well as binding assays to identify and validate a PcG/trxG response element (PRE), PRE1 which acts to reorganize the surrounding chromatin, regulating S5-dependent expression. To our knowledge, PRE1 is the first validated vertebrate PcG/trxG response element. Thus, PRE1 provides a springboard for further exploration of the mechanisms governing chromatin remodeling.

Diss. (sammanfattning) Stockholm : Karol. inst., 2004. / Härtill 6 uppsatser.

Thesis (Ph. D.)--University of Virginia, 2008. / Title from title page. Includes bibliographical references. Also available online through Digital Dissertations.

Ng Lui. / Thesis (M.Phil.)--Chinese University of Hong Kong, 2006. / Includes bibliographical references (leaves 243-257). / Abstracts in English and Chinese. / Abstract --- p.i_iii / Abstract (Chinese version) --- p.iv-v / Acknowledgements --- p.vi / Table of Contents --- p.vii-xvii / List of Abbreviations --- p.xviii-xx / List of Figures --- p.xxi-xxvi / List of Tables --- p.xxvii / Chapter Chapter 1 --- Introduction --- p.1 / Chapter 1.1 --- Peroxisome Proliferators (PPs) --- p.1 / Chapter 1.2 --- Peroxisome proliferator-activated receptors (PPARs) --- p.3 / Chapter 1.2.1 --- What are PPARs? --- p.3 / Chapter 1.2.2 --- PPAR isoforms --- p.3 / Chapter 1.2.2.1 --- PPARp/δ --- p.3 / Chapter 1.2.2.2 --- PPARγ --- p.4 / Chapter 1.2.2.3 --- PPARα --- p.5 / Chapter 1.2.3 --- PPARα target genes --- p.5 / Chapter 1.2.3.1 --- Transcriptional regulation --- p.5 / Chapter 1.2.3.2 --- PPRE --- p.6 / Chapter 1.2.4 --- Physiological roles --- p.9 / Chapter 1.2.4.1 --- Lipid metabolism --- p.9 / Chapter 1.2.4.1.1 --- Cellular fatty acid uptake and fatty acid activation --- p.9 / Chapter 1.2.4.1.2 --- Intracellular fatty acid transport --- p.11 / Chapter 1.2.4.1.3 --- Mitochondrial fatty acid uptake --- p.12 / Chapter 1.2.4.1.4 --- Mitochondrial fatty-acid P-oxidation / Chapter 1.2.4.1.5 --- Peroxisomal fatty acid uptake --- p.13 / Chapter 1.2.4.1.6 --- Peroxisomal fatty acid oxidation --- p.13 / Chapter 1.2.4.1.7 --- Micorsomal co-hydroxylation of fatty acids --- p.14 / Chapter 1.2.4.1.8 --- Ketogenesis --- p.15 / Chapter 1.2.4.1.9 --- Bile acid metabolism --- p.15 / Chapter 1.2.4.1.10 --- Lipoprotein metabolism --- p.17 / Chapter 1.2.4.1.11 --- Hepatic lipogenesis --- p.18 / Chapter 1.2.4.2 --- Glucose metabolism --- p.19 / Chapter 1.2.4.2.1 --- Glycogenolysis --- p.19 / Chapter 1.2.4.2.2 --- Glycolysis --- p.20 / Chapter 1.2.4.2.3 --- Gluconeogenesis --- p.20 / Chapter 1.2.4.3 --- Urea cycle --- p.21 / Chapter 1.2.4.4 --- Biotransformation --- p.22 / Chapter 1.2.4.5 --- Inflammation --- p.23 / Chapter 1.2.4.6 --- Acute phase response --- p.23 / Chapter 1.2.5 --- Toxicological roles --- p.24 / Chapter 1.2.5.1 --- PPs induce hepatocarcinoma formation through PPARα --- p.24 / Chapter 1.2.5.2 --- Mechanism of PPARa-mediated PP-induced hepatocarcinoma --- p.25 / Chapter 1.2.5.2.1 --- Oxidative stress --- p.25 / Chapter 1.2.5.2.2 --- Hepatocellular proliferation and inhibition of apoptosis --- p.26 / Chapter 1.3 --- Discovery of novel PPARα target genes --- p.27 / Chapter 1.3.1 --- Peroxisome proliferator and starvation-induced gene (PPSIG) --- p.28 / Chapter 1.3.1.1 --- PPSIG is a putative PPARa target gene --- p.28 / Chapter 1.3.1.2 --- Examination of PPSIG FDD fragment cDNA sequence --- p.28 / Chapter 1.4 --- Objectives --- p.32 / Chapter Chapter 2 --- Materials and Methods --- p.38 / Chapter 2.1 --- Cloning of the full-length mouse PPSIG cDNA --- p.38 / Chapter 2.1.1 --- Rapid amplification of cDNA ends (RACE) --- p.38 / Chapter 2.1.1.1 --- Total RNA extraction --- p.38 / Chapter 2.1.1.1.1 --- Materials --- p.38 / Chapter 2.1.1.1.2 --- Methods --- p.38 / Chapter 2.1.1.2 --- Primers design --- p.39 / Chapter 2.1.1.3 --- 5' and 3' cDNA ends amplification --- p.42 / Chapter 2.1.1.3.1 --- Materials --- p.42 / Chapter 2.1.1.3.2 --- Methods --- p.42 / Chapter 2.1.2 --- Subcloning of 5' and 3'RACED products --- p.45 / Chapter 2.1.2.1 --- Ligation and transformation --- p.45 / Chapter 2.1.2.1.1 --- Materials --- p.45 / Chapter 2.1.2.1.2 --- Methods --- p.46 / Chapter 2.1.2.2 --- Screening of the recombinants --- p.48 / Chapter 2.1.2.2.1 --- PhenoI:chloroform test --- p.48 / Chapter 2.1.2.2.1.1 --- Materials --- p.48 / Chapter 2.1.2.2.1.2 --- Methods --- p.48 / Chapter 2.1.2.2.2 --- Restriction enzyme digestion --- p.48 / Chapter 2.1.2.2.2.1 --- Materials --- p.48 / Chapter 2.1.2.2.2.2 --- Methods --- p.49 / Chapter 2.1.3 --- DNA sequencing of the 5'and 3'RACED subclones --- p.49 / Chapter 2.1.4 --- Northern blot analysis using PPSIG 5' and 3' RACED cDNA as probes --- p.52 / Chapter 2.1.4.1 --- RNA sample preparation --- p.52 / Chapter 2.1.4.1.1 --- Materials --- p.52 / Chapter 2.1.4.1.2 --- Methods --- p.52 / Chapter 2.1.4.2 --- Formaldehyde-agarose gel electrophoresis and blotting of RNA --- p.52 / Chapter 2.1.4.2.1 --- Materials --- p.52 / Chapter 2.1.4.2.2 --- Methods --- p.53 / Chapter 2.1.4.3 --- Probe preparation --- p.55 / Chapter 2.1.4.3.1 --- DIG labeling of RNA probe from 5'RACED PPSIG cDN A subclone 5'#32 --- p.55 / Chapter 2.1.4.3.1.1 --- Materials --- p.55 / Chapter 2.1.4.3.1.2 --- Methods --- p.55 / Chapter 2.1.4.3.2 --- PCR DIG labeling of 3´ة RACED PPSIG cDNA subclone 3' #12 --- p.56 / Chapter 2.1.4.3.2.1 --- Materials --- p.56 / Chapter 2.1.4.3.2.2 --- Methods --- p.57 / Chapter 2.1.4.4 --- Hybridization --- p.57 / Chapter 2.1.4.4.1 --- Materials --- p.57 / Chapter 2.1.4.4.2 --- Methods --- p.57 / Chapter 2.1.4.5 --- Post-hybridization washing and colour development --- p.59 / Chapter 2.1.4.5.1 --- Materials --- p.59 / Chapter 2.1.4.5.2 --- Methods --- p.59 / Chapter 2.2 --- Cloning of the PPSIG genomic DNA --- p.61 / Chapter 2.2.1 --- Screening of bacterial artificial chromosome (BAC) clones --- p.61 / Chapter 2.2.1.1 --- Screening of a mouse genomic library --- p.61 / Chapter 2.2.1.2 --- "Purification of BAC DNA by solution I, II,III" --- p.61 / Chapter 2.2.1.2.1 --- Materials --- p.61 / Chapter 2.2.1.2.2 --- Methods --- p.61 / Chapter 2.2.2 --- Confirmation of PPSIG genomic BAC clones --- p.64 / Chapter 2.2.2.1 --- Genomic Southern blot analysis --- p.64 / Chapter 2.2.2.1.1 --- Agarose gel electrophoresis and blotting of BAC DNA --- p.64 / Chapter 2.2.2.1.1.1 --- Materials --- p.64 / Chapter 2.2.2.1.1.2 --- Methods --- p.64 / Chapter 2.2.2.1.2 --- DIG labeling of DNA probe by random priming --- p.65 / Chapter 2.2.2.1.2.1 --- Materials --- p.65 / Chapter 2.2.2.1.2.2 --- Methods --- p.65 / Chapter 2.2.2.1.3 --- Hybridization --- p.66 / Chapter 2.2.2.1.4 --- Post-hybridization washing and colour development --- p.66 / Chapter 2.2.2.2 --- EcoR I digestion --- p.67 / Chapter 2.2.2.2.1 --- Materials --- p.67 / Chapter 2.2.2.2.2 --- Methods --- p.67 / Chapter 2.2.2.3 --- Large scale preparation of BAC DNA --- p.67 / Chapter 2.2.2.3.1 --- Materials --- p.67 / Chapter 2.2.2.3.2 --- Methods --- p.68 / Chapter 2.2.3 --- Determination of PPSIG genomic sequences --- p.68 / Chapter 2.2.3.1 --- Primers design --- p.68 / Chapter 2.2.3.2 --- PCR --- p.73 / Chapter 2.2.3.2.1 --- Materials --- p.73 / Chapter 2.2.3.2.2 --- Methods --- p.73 / Chapter 2.2.3.3 --- Subcloning of the PPSIG genomic fragments --- p.73 / Chapter 2.2.3.3.1 --- Ligation and transformation --- p.73 / Chapter 2.2.3.3.2 --- PCR screening --- p.74 / Chapter 2.2.3.3.2.1 --- Materials --- p.74 / Chapter 2.2.3.3.2.2 --- Methods --- p.74 / Chapter 2.2.3.4 --- DNA sequencing --- p.75 / Chapter 2.3 --- Cloning of PPSIG-promoter reporter constructs --- p.75 / Chapter 2.3.1 --- Amplification of PPSIG 5'-flanking fragment by PCR --- p.75 / Chapter 2.3.1.1 --- Materials --- p.75 / Chapter 2.3.1.2 --- Methods --- p.75 / Chapter 2.3.2 --- Preparation of pGL3-Basic vector DNA --- p.81 / Chapter 2.3.2.1 --- Materials --- p.81 / Chapter 2.3.2.2 --- Methods --- p.81 / Chapter 2.3.3 --- Ligation and transformation --- p.84 / Chapter 2.3.3.1 --- Materials --- p.84 / Chapter 2.3.3.2 --- Methods --- p.84 / Chapter 2.3.4 --- Screening and confirmation of recombinants --- p.85 / Chapter 2.3.4.1 --- Materials --- p.85 / Chapter 2.3.4.2 --- Methods --- p.85 / Chapter 2.4 --- Cloning of PPSIG 5'-deletion promoter constructs --- p.87 / Chapter 2.4.1 --- Deletion of target fragments by restriction enzyme digestion --- p.87 / Chapter 2.4.1.1 --- Materials --- p.87 / Chapter 2.4.1.2 --- Methods --- p.88 / Chapter 2.4.2 --- Ligation and transformation --- p.90 / Chapter 2.4.2.1 --- Materials --- p.90 / Chapter 2.4.2.2 --- Methods --- p.90 / Chapter 2.4.3 --- Screening and confirmation of recombinants --- p.91 / Chapter 2.5 --- Cloning of PPSIG-PPRE reporter constructs --- p.91 / Chapter 2.5.1 --- Amplification of PPSIG-PPRE fragments --- p.91 / Chapter 2.5.1.1 --- Materials --- p.91 / Chapter 2.5.1.2 --- Methods --- p.93 / Chapter 2.5.2 --- Preparation of pGL3-Basic vector DNA --- p.96 / Chapter 2.5.2.1 --- Materials --- p.96 / Chapter 2.5.2.2 --- Methods --- p.96 / Chapter 2.5.3 --- Ligation and transformation --- p.97 / Chapter 2.5.3.1 --- Materials --- p.97 / Chapter 2.5.3.2 --- Methods --- p.97 / Chapter 2.5.4 --- Screening and confirmation of recombinants --- p.97 / Chapter 2.6 --- Cloning of PPSIG-PPRE deletion construct --- p.101 / Chapter 2.6.1 --- Deletion of PPRE fragment by Stu I/Xho I digestion --- p.101 / Chapter 2.6.1.1 --- Materials --- p.101 / Chapter 2.6.1.2 --- Methods --- p.101 / Chapter 2.6.2 --- "Ligation, transformation, screening and confirmation of recombinants" --- p.103 / Chapter 2.7 --- Construction of PPSIG-PPRE-deletion and PPSIG- PPRE-mutation constructs by site-directed mutagenesis --- p.105 / Chapter 2.7.1 --- Primers design --- p.105 / Chapter 2.7.2 --- Amplification of the left and right halves of the PPRE-deletion and PPRE-mutation constructs by PCR --- p.109 / Chapter 2.7.2.1 --- Materials --- p.109 / Chapter 2.7.2.2 --- Methods --- p.109 / Chapter 2.7.3 --- "Ligation, Dpn I digestion and transformation" --- p.110 / Chapter 2.7.3.1 --- Materials --- p.110 / Chapter 2.7.3.2 --- Methods --- p.110 / Chapter 2.7.4 --- Screening and confirmation of recombinants --- p.111 / Chapter 2.7.4.1 --- Materials --- p.111 / Chapter 2.7.4.2 --- Methods --- p.111 / Chapter 2.8 --- Cloning of mouse malonyl-CoA decarboxylase (MCD) and rat acyl-CoA binding protein (ACBP) PPRE reporter constructs --- p.112 / Chapter 2.8.1 --- Preparation of mouse and rat genomic DNA --- p.112 / Chapter 2.8.1.1 --- Materials --- p.112 / Chapter 2.8.1.2 --- Methods --- p.113 / Chapter 2.8.2 --- Amplification of MCD and ACBP PPRE fragments by PCR --- p.113 / Chapter 2.8.2.1 --- Materials --- p.113 / Chapter 2.8.2.2 --- Methods --- p.114 / Chapter 2.8.3 --- Ligation and transformation --- p.117 / Chapter 2.8.4 --- Screening and confirmation of recombinants --- p.117 / Chapter 2.9 --- Cloning of mPPARα and mRXRα expression plasmids --- p.119 / Chapter 2.9.1 --- RT-PCR of mouse PPARα and RXRa cDNAs --- p.119 / Chapter 2.9.1.1 --- Materials --- p.119 / Chapter 2.9.1.2 --- Methods --- p.119 / Chapter 2.9.2 --- Preparation of pSG5 vector DNA --- p.123 / Chapter 2.9.2.1 --- Materials --- p.123 / Chapter 2.9.2.2 --- Methods --- p.123 / Chapter 2.9.3 --- Ligation and transformation --- p.125 / Chapter 2.9.3.1 --- Materials --- p.125 / Chapter 2.9.3.2 --- Methods --- p.125 / Chapter 2.9.4 --- Screening and confirmation of recombinants --- p.125 / Chapter 2.9.4.1 --- Materials --- p.125 / Chapter 2.9.4.2 --- Methods --- p.126 / Chapter 2.10 --- Transient transfection and reporter assays --- p.128 / Chapter 2.10.1 --- Cell culture and transient transfection --- p.128 / Chapter 2.10.1.1 --- Materials --- p.128 / Chapter 2.10.1.2 --- Methods --- p.128 / Chapter 2.10.2 --- Assay for reporter construct luciferase activity --- p.131 / Chapter 2.10.2.1 --- Materials --- p.131 / Chapter 2.10.2.2 --- Methods --- p.131 / Chapter 2.11 --- Electrophoretic mobility-shift assay (EMSA) --- p.133 / Chapter 2.11.1 --- In vitro transcription/translation --- p.133 / Chapter 2.11.1.1 --- Materials --- p.133 / Chapter 2.11.1.2 --- Methods --- p.133 / Chapter 2.11.2 --- Preparation of AML-12 nuclear extract --- p.134 / Chapter 2.11.3 --- Preparation of DIG-labeled PPSIG-PPRE oligonucleotides --- p.136 / Chapter 2.11.3.1 --- Oligonucleotides design --- p.136 / Chapter 2.11.3.2 --- Annealing of single-stranded oligonucleotides to form double- stranded oligonucleotides --- p.136 / Chapter 2.11.3.2.1 --- Materials --- p.136 / Chapter 2.11.3.2.2 --- Methods --- p.138 / Chapter 2.11.3.3 --- 3' end labeling of the double-stranded oligonucleotides --- p.138 / Chapter 2.11.3.3.1 --- Materials --- p.138 / Chapter 2.11.3.3.2 --- Methods --- p.138 / Chapter 2.11.3.4 --- Testing the labeling efficiency of the double-stranded oligonucleoides --- p.139 / Chapter 2.11.3.4.1 --- Materials --- p.139 / Chapter 2.11.3.4.2 --- Methods --- p.139 / Chapter 2.11.4 --- Preparation of unlabeled oligonucleotides as competitors --- p.140 / Chapter 2.11.5 --- Binding reactions --- p.142 / Chapter 2.11.5.1 --- Perform with in vitro transcribed/translated proteins --- p.142 / Chapter 2.11.5.1.1 --- Materials --- p.142 / Chapter 2.11.5.1.2 --- Methods --- p.142 / Chapter 2.11.5.2 --- Perform with AML-12 nuclear extracts --- p.144 / Chapter 2.11.5.2.1 --- Materials --- p.144 / Chapter 2.11.5.2.2 --- Methods --- p.144 / Chapter 2.11.6 --- Detection of shift-up pattern --- p.145 / Chapter 2.11.6.1 --- Materials --- p.145 / Chapter 2.11.6.2 --- Methods --- p.145 / Chapter 2.12 --- Statistical analysis --- p.146 / Chapter Chapter 3 --- Results --- p.147 / Chapter 3.1 --- PPSIG cDNA sequence analysis --- p.147 / Chapter 3.1.1 --- Cloning of PPSIG full-length cDNA sequence --- p.147 / Chapter 3.1.2 --- Northern blot analysis of PPSIG --- p.160 / Chapter 3.1.3 --- "Comparison of PPSIG, Riken cDNA 0610039N19 and all-trans-13'14-dihydroretinol saturase cDNA sequences" --- p.163 / Chapter 3.2 --- PPSIG genomic sequence analysis --- p.166 / Chapter 3.2.1 --- Screening of the PPSIG BAC clone --- p.166 / Chapter 3.2.2 --- Cloning of PPSIG genomic fragments --- p.167 / Chapter 3.2.3 --- Examination of PPSIG genomic organization --- p.170 / Chapter 3.2.3.1 --- "Comparison of PPSIG, Riken cDNA 0610039N19 and all-trans-13'14-dihydroretinol saturase genomic sequence" --- p.177 / Chapter 3.3 --- Characterization of the 5'-flanking region of PPSIG --- p.184 / Chapter 3.4 --- Identification of a functional PPRE in the intron 1 of PPSIG gene --- p.201 / Chapter 3.5 --- Gel shift analysis of PPARa/RXRa heterodimer to PPSIG-PPRE --- p.222 / Chapter Chapter 4 --- Discussion --- p.234 / Chapter Chapter 5 --- Future studies --- p.241 / References --- p.243 / Appendix A Seating plan of transfection experiments (24-wells) / Chapter A1 --- Transfection experiment to study PPSIG-promoter reporter constructs --- p.258 / Chapter A2 --- Transfection experiment to study the PPSIG- promoter deletion constructs --- p.259 / Chapter A3 --- Transfection experiment to study the PPSIG-PPRE reporter constructs --- p.260 / Chapter A4 --- Transfection experiment to study PPSIG-PPRE- deletion and PPSIG-PPRE-mutation constructs --- p.262 / Appendix B Alignment result of RACE clone DNAs --- p.265 / Chapter B1 --- Alignment result of 5´ة#7 --- p.265 / Chapter B2 --- Alignment result of 5'#11 --- p.267 / Chapter B3 --- Alignment result of 5'#12 --- p.269 / Chapter B4 --- Alignment result of 5´ة#16 --- p.271 / Chapter B5 --- Alignment result of 5´ة#20 --- p.274 / Chapter B6 --- Alignment result of 5´ة#31 --- p.276 / Chapter B7 --- Alignment result of 5´ة#32 --- p.278 / Chapter B8 --- Consensus sequence of each 5'RACED clone --- p.280 / Chapter B9 --- Alignment result of all 5'RACE clones consensus sequence --- p.287 / Chapter B10 --- Alignment result of 3´ة#2 --- p.290 / Chapter B11 --- Alignment result of 3´ة#3 --- p.291 / Chapter B12 --- Alignment result of 3´ة#14 --- p.292 / Chapter B13 --- Alignment result of 3´ة#5 --- p.293 / Chapter B14 --- Alignment result of 3´ة#6 --- p.294 / Chapter B15 --- Alignment result of 3´ة#8 --- p.295 / Chapter B16 --- Alignment result of 3´ة#10 --- p.297 / Chapter B17 --- Alignment result of 3´ة#11 --- p.298 / Chapter B18 --- Alignment result of 3´ة#12 --- p.299 / Chapter B19 --- Alignment result of 3´ة#16 --- p.301 / Chapter B20 --- Alignment result of 3´ة#22 --- p.302 / Chapter B21 --- Alignment result of 3´ة#25 --- p.303 / Chapter B22 --- Consensus sequence of each 3'RACED clone --- p.305 / Chapter B23 --- Alignment result of all 3' RACE clones consensus sequence --- p.310 / Appendix C DNA sequencing and alignment result of PPSIG genomic fragments --- p.312 / Chapter C1 --- Exon 1 to exon 2 --- p.312 / Chapter C2 --- Exon 2 to exon 3 --- p.315 / Chapter C3 --- Exon 3 to exon 4 --- p.316 / Chapter C4 --- Exon 4 to exon 5 --- p.318 / Chapter C5 --- Exon 5 to exon 6 --- p.319 / Chapter C6 --- Exon 6 to exon 7 --- p.321 / Chapter C7 --- Exon 7 to exon 8 --- p.322 / Chapter C8 --- Exon 8 to exon 9 --- p.323 / Chapter C9 --- Exon 9 to exon 10 --- p.324 / Chapter C10 --- Exon 10 to exon 11 --- p.325 / Chapter C11 --- Exon 11 to downstream --- p.326 / Chapter C12 --- Consensus sequence of each BAC genomic DNA fragment --- p.328 / Chapter C13 --- The alignment result of all the PPSIG genomic sequence --- p.335 / Appendix D DNA sequencing and alignment result of constructs --- p.347 / Chapter D1 --- "pGL3-PPSIG (-2936/+119), pGL3-PPSIG (-1534/+119), pGL3-PPSIG (-879/+119) and pGL3- PPSIG (-375/+119) reporter constructs DNA sequencing and alignment result" --- p.347 / Chapter D2 --- pSG5-PPARa expression plasmid DNA sequencing and alignment result --- p.351 / Chapter D3 --- pSG5-RXRa expression plasmid DNA sequencing and alignment result --- p.353 / Chapter D4 --- pGL3-MCD reporter constructs DNA sequencing and alignment result --- p.355 / Chapter D5 --- pGL3-PPSIG (-229/+435) reporter construct DNA sequencing and alignment result --- p.356 / Chapter D6 --- pGL3-PPSIG (+94/+435) and pGL3-PPSIG (+94/+190) reporter constructs DNA sequencing and alignment result --- p.357 / Chapter D7 --- pGL3-PPSIG (-229/+3031) reporter construct DNA sequencing and alignment result --- p.358 / Chapter D8 --- pGL3-PPSIG (+94/+3031) reporter construct DNA sequencing and alignment result --- p.360 / Chapter D9 --- pGL3-ACBP reporter construct DNA sequencing and alignment result --- p.362 / Chapter D10 --- PPSIG-PPRE-deletion and PPSIG-PPRE-mutation constructs DNA sequencing and alignment result --- p.363

Thesis (Ph. D.)--University of Missouri--Columbia, 2001. / "May 2001." Typescript. Vita. Includes bibliographical references (leaves 88-99). Also available on the Internet.

Thesis (Ph. D.)--University of Missouri--Columbia, 2001. / Typescript. Vita. Includes bibliographical references (leaves 88-99). Also available on the Internet.

No description available.

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.

As partículas eliminadas na exaustão do diesel (DEP) são importantes fontes diárias de partículas inaladas, responsáveis por gerar espécies reativas de oxigênio no sistema respiratório, fazendo com que as células ativem mecanismos de defesa, como o sistema Keap1-Nrf2 e a autofagia. Para investigar o papel do Nrf2 no processo de autofagia induzida pelas DEPs, BEAS-2B foram expostas às DEP, coletadas diretamente de um motor a diesel. BEAS-2B foram tratadas com sulforafano, bafilomicina e EBSS para testar a relação entre as vias autofágica e antioxidante. A quantidade relativa de mRNA foi verificada por RT-PCR para os seguintes genes: Nrf2, NQO1, HO-1, p62, Atg5 e LCB3. A seguir, BEAS-2B foram transfectadas com RNA silenciador (siRNA) para Nrf2, expostas ou não às DEPs (10 e 50 micro g/mL por 1h e 2 h), e mRNA detectado por RT-PCR e Western blot para proteínas. Bafilomicina (inibidor de autofagia) mostrou uma diminuição significativa nos marcadores antioxidantes Nrf2 (p = 0,024), HO-1 (p = 0,002) e NQO1 (p = 0,003), enquanto sulforafano (ativador de Nrf2) aumentou os marcadores autofágicos LC3B (p = 0,004) e Atg5 (p = 0,007). BEAS-2B expostas às DEP na concentração de 50 micro g/mL por 2hs mostraram um aumento significativo nos genes autofágicos LC3B (p = 0,018) e p62 (p = 0,007) e nos genes da via antioxidante Nrf2 (p = 0,007) e NQO1 (p = 0,025). Houve uma diminuição significativa no mRNA de LC3B (p < 0,001), p62 (p = 0,001) e Atg5 (p = 0,024) nas células transfectadas com siRNA, expostas ou não à DEP. Western blotting mostrou uma redução das proteínas Nrf2, p62 e LC3II nas BEAS-2B siRNA, indicando que a exposição ao silenciamento de Nrf2 modificou a expressão de marcadores de autofagia (R < 1). Os resultados deste estudo mostram que, em células brônquicas expostas às DEP, o sistema Nrf2 e a autofagia trabalham em conjunto para tentar manter a homeostase celular / Diesel Exhaust Particles (DEPs) are main sources of daily inhaled particles, responsible for generating reactive oxygen species in the respiratory system, and causing the cells to activate defense mechanisms, such as the Keap1-Nrf2 system and autophagy. In order to investigate the role of Nrf2 in Dep-induced autophagy, BEAS-2B cells collected directly from a diesel engine were exposed to DEP and treated with sulforaphane, bafilomycin and BESS to test the relationship between autophagic and antioxidant pathways. The relative amount of mRNA was verified by RT-PCR for the following genes: Nrf2, NQO1, HO-1, p62, Atg5 and LCB3. Next, BEAS-2B cells were transfected with silencer RNA (siRNA) specific to Nrf2, exposed or not to DEPs (10 and 50 micro g/mL 1h and 2hs), and mRNA detected by RT-PCR and Western blotting for protein. Bafilomycin ( autophagy inhibitor) showed a significant decrease in the antioxidant markers Nrf2 (p=0.024), HO-1 (p = 0.002) and NQO1 (p = 0.003), whereas sulforaphane (Nrf2 activator) increased the expression levels of autophagic markers LC3B (p=0.004) and Atg5 (p=0.007). BEAS-2B exposed to DEP at a concentration of 50 micro g/mL for 2hs showed a significant increase in autophagic genes LC3B (p=0.018) and p62 (p=0.007),and in the antioxidant pathway markers Nrf2 (p=0.007) and NQO1 (p=0.025). There was a significant decrease in mRNA of the LC3B (p < 0.001), p62 (p=0.001) and Atg5 (p=0.024) in cells transfected with siRNA, exposed or not to DEP. Western blotting showed a reduction of Nrf2, p62 and LC3II proteins in BEAS-2B transfected with siRNA, indicating that Nrf2 silencedexposed to DEP modulated the expression of autophagy markers (R < 1). The results of this study show that, in bronchial cells exposed to DEP, the Nrf2 system and autophagy work together in order to try to maintain cellular homeostasis