@phdthesis{Esterlechner2013, author = {Esterlechner, Jasmina}, title = {Role of the DREAM complex in mouse embryonic stem cells and identification of ZO-2 as a new LIN9 interacting protein}, url = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-90440}, school = {Universit{\"a}t W{\"u}rzburg}, year = {2013}, abstract = {The DREAM complex plays an important role in regulation of gene expression during the cell cycle. It was previously shown that the DREAM subunits LIN9 and B-MYB are required for early embryonic development and for the maintenance of the inner cell mass in vitro. In this work the effect of LIN9 or B-MYB depletion on embryonic stem cells (ESC) was examined. It demonstrates that LIN9 and B-MYB knock down changes the cell cycle distribution of ESCs and results in an accumulation of cells in G2 and M and in an increase of polyploid cells. By using genome-wide expression studies it was revealed that the depletion of LIN9 leads to downregulation of mitotic genes and to upregulation of differentiation-specific genes. ChIP-on chip experiments determined that mitotic genes are direct targets of LIN9 while lineage specific markers are regulated indirectly. Importantly, depletion of LIN9 does not alter the expression of the pluripotency markers Sox2 and Oct4 and LIN9 depleted ESCs retain alkaline phosphatase activity. I conclude that LIN9 is essential for proliferation and genome stability of ESCs by activating genes with important functions in mitosis and cytokinesis. The exact molecular mechanisms behind this gene activation are still unclear as no DREAM subunit features a catalytically active domain. It is assumed that DREAM interacts with other proteins or co-factors for transcriptional activation. This study discovered potential binding proteins by combining in vivo isotope labeling of proteins with mass spectrometry (MS) and further analysed the identified interaction of the tight junction protein ZO-2 with DREAM which is cell cycle dependent and strongest in S-phase. ZO-2 depletion results in reduced cell proliferation and decreased G1 gene expression. As no G2/M genes, typical DREAM targets, are affected upon ZO-2 knock down, it is unlikely that ZO-2 binding is needed for a functional DREAM complex. However, this work demonstrates that with (MS)-based quantitative proteomics, DREAM interacting proteins can be identified which might help to elucidate the mechanisms underlying DREAM mediated gene activation.}, subject = {Zellzyklus}, language = {en} } @phdthesis{Banaszek2013, author = {Banaszek, Agnes}, title = {Dual Antigen-Restricted Complementation of a Two-Part Trispecific Antibody for Targeted Immunotherapy of Blood Cancer}, url = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-90174}, school = {Universit{\"a}t W{\"u}rzburg}, year = {2013}, abstract = {Cancer cells frequently escape from immune surveillance by down-regulating two important components of the immune defence: antigen-presenting MHC and costimulatory molecules. Therefore several novel anti-tumour compounds that aim to assist the immune system in recognising and fighting cancer are currently under development. Recombinant bispecific antibodies represent one group of such novel therapeutics. They target two different antigens and recruit cytotoxic effector cells to tumour cells. For cancer immunotherapy, bispecific T cell-engaging antibodies are already well characterised. These antibodies target a tumour-associated antigen and CD3ε, the constant molecule of the T cell receptor complex. On the one hand, this study presents the development of a bispecific antibody targeting CD3ε and the rhabdomyosarcoma-associated fetal acetylcholine receptor. On the other hand, it describes a novel two-part trispecific antibody format for the treatment of leukaemia and other haematological malignancies in the context of haematopoietic stem cell transplantation (HSCT). For HSCT, an HLA-identical donor is preferred, but very rarely available. In an HLA-mismatched setting, the HLA disparity could be exploited for targeted cancer treatment. In the present study, a two-part trispecific HLA-A2 × CD45 × CD3 antibody was developed for potential cases in which the patient is HLA-A2-positive, but the donor is not. This holds true for about half the cases in Germany, since HLA-A2 is the most common HLA molecule found here. Combinatorial targeting of HLA-A2 and the leucocyte-common antigen CD45 allows for highly specific dual-antigen restricted tumour targeting. More precisely, two single-chain antibody constructs were developed: i) a single-chain variable fragment (scFv) specific for HLA-A2, and ii) a scFv against CD45, both linked to the VL and the VH domain of a CD3ε-specific antibody, respectively. It turned out that, after the concomitant binding of these constructs to the same HLA-A2- and CD45-expressing cell, the unpaired variable domains of a CD3ε-specific antibody assembled to a functional scFv. In a therapeutic situation, this assembly should exclusively occur on the recipient's blood cancer cells, leading to T cell-mediated cancer cell destruction. In this way, a relapse of disease might be prevented, and standard therapy (radiation and chemotherapy) might be omitted. For both approaches, the antibody constructs were periplasmically expressed in E. coli, purified via His tag, and biochemically characterised. Their binding to the respective targets was proven by flow cytometry. The stimulatory properties of the antibodies were assayed by measuring IL-2 release after incubation with T cells and antigen-expressing target cells. Both the bispecific antibody against rhabdomyosarcoma and the assembled trispecific antibody against blood cancer mediated T-cell activation in a concentration-dependent manner at nanomolar concentrations. For the trispecific antibody, this effect indeed proved to be dual antigen-restricted, as it could be blocked by prior incubation of either HLA-A2- or CD45-specific scFv and did not occur on single-positive (CD45+) or double-negative (HLA-A2- CD45-) target cells. Furthermore, antibodies from both approaches recruited T cells for tumour cell destruction in vitro.}, subject = {Immuntherapie}, language = {en} } @phdthesis{Reil2013, author = {Reil, Michael}, title = {Essentielle Rollen des LEM-Dom{\"a}nen Proteins MAN1 w{\"a}hrend der Organentwicklung von Xenopus laevis und {\"u}berlappende Funktionen von Emerin}, url = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-85105}, school = {Universit{\"a}t W{\"u}rzburg}, year = {2013}, abstract = {Mutationen in Genen, die f{\"u}r Kernh{\"u}llproteine codieren sind mit einer stetig zunehmenden Anzahl menschlicher Erkrankungen verbunden, die als Envelopathien bezeichnet werden. Erstaunlicherweise betrifft die Pathologie dieser Krankheiten spezifische Gewebe und Organe, obwohl entsprechende Proteine meist ubiquit{\"a}r exprimiert werden. So f{\"u}hren beispielsweise Defekte in Emerin, einem Protein der inneren Kernh{\"u}lle, zur X-chromosomalen Emery- Dreifuss Muskeldystrophie (EDMD). Diese Krankheit ist durch Muskelschw{\"a}che oder - schwund gekennzeichnet. Defekte im Kernh{\"u}llprotein MAN1 sind dagegen mit Krankheiten verbunden, die Knochen- und Hautgewebe betreffen. Interessanterweise besitzen beide Proteine eine evolution{\"a}r hoch konservierte Dom{\"a}ne, die sog. LEM-Dom{\"a}ne. LEM-Dom{\"a}nen Proteine k{\"o}nnen mit der Kernlamina interagieren, ebenso mit dem sog. Barrier-to- Autointegration Factor (BAF) sowie mit zahlreichen Transkriptionsfaktoren. Dennoch ist die funktionelle Rolle der LEM-Dom{\"a}nen Proteine bis dato nicht vollst{\"a}ndig aufgekl{\"a}rt. In der vorliegenden Studie sollten daher die Funktionen von MAN1 und Emerin w{\"a}hrend der Fr{\"u}hentwicklung von Xenopus laevis untersucht werden. Vorangehende Untersuchungen zeigten, dass Mikroinjektionen von XMAN1- Antik{\"o}rpern in Zwei-Zell-Stadien befruchteter Eizellen zu einem Arrest der Zellteilung in der injizierten Blastomere f{\"u}hrten. Da dabei eine St{\"o}rung der Kernh{\"u}llbildung spekuliert wurde, sollte durch Antik{\"o}rper-vermittelter Inhibition von XMAN1 die Bildung von in vitro Kernen im Xenopus Eiextrakt untersucht werden. Dabei wurden Kerne beobachtet, die dekondensiertes Chromatin zeigten, bei denen jedoch eine Fusion von Membranvesikeln zu einer durchgehenden Kernh{\"u}lle nicht stattgefunden hatte. Fr{\"u}here Charakterisierungen von MAN1 und Emerin zeigten unterschiedliche Expressionsmuster w{\"a}hrend der Entwicklung von X. laevis. Da XMAN1 ubiquit{\"a}r exprimiert und Xemerin jedoch erstmals ab Stadium 41 nachweisbar ist, war es mittels Mikroinjektion von Xemerin m{\"o}glich zu zeigen, dass es in der Lage ist den Arrest der Zellteilung zu verhindern. Es wurde daher die These aufgestellt, dass MAN1 und Emerin w{\"a}hrend der Fr{\"u}hentwicklung von Xenopus {\"u}berlappende Funktionen besitzen. Um diese These zu pr{\"u}fen, wurde zun{\"a}chst unter Verwendung des Proximity Ligation Assays untersucht, ob beide Proteine miteinander interagieren k{\"o}nnen. Mit Hilfe dieser Methode konnte gezeigt werden, dass Interaktionen beider Proteine innerhalb der Kernh{\"u}lle lokalisieren. Die Interaktionen blieben w{\"a}hrend der Mitose bestehen und waren erst wieder zum Ende der Mitose in der Kernh{\"u}lle nachweisbar. Diese Resultate deuten daher darauf hin, dass XMAN1/Xemerin-Interaktionen w{\"a}hrend der ...}, subject = {Organogenese}, language = {de} } @phdthesis{EngelhardtgebChristiansen2013, author = {Engelhardt [geb. Christiansen], Frauke}, title = {Synaptic Connectivity in the Mushroom Body Calyx of Drosophila melanogaster}, url = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-85058}, school = {Universit{\"a}t W{\"u}rzburg}, year = {2013}, abstract = {Learning and memory is considered to require synaptic plasticity at presynaptic specializations of neurons. Kenyon cells are the intrinsic neurons of the primary olfactory learning center in the brain of arthropods - the mushroom body neuropils. An olfactory mushroom body memory trace is supposed to be located at the presynapses of Kenyon cells. In the calyx, a sub-compartment of the mushroom bodies, Kenyon cell dendrites receive olfactory input provided via projection neurons. Their output synapses, however, were thought to reside exclusively along their axonal projections outside the calyx, in the mushroom body lobes. By means of high-resolution imaging and with novel transgenic tools, we showed that the calyx of the fruit fly Drosophila melanogaster also comprised Kenyon cell presynapses. At these presynapses, synaptic vesicles were present, which were capable of neurotransmitter release upon stimulation. In addition, the newly identified Kenyon cell presynapses shared similarities with most other presynapses: their active zones, the sites of vesicle fusion, contained the proteins Bruchpilot and Syd-1. These proteins are part of the cytomatrix at the active zone, a scaffold controlling synaptic vesicle endo- and exocytosis. Kenyon cell presynapses were present in γ- and α/β-type KCs but not in α/β-type Kenyon cells. The newly identified Kenyon cell derived presynapses in the calyx are candidate sites for an olfactory associative memory trace. We hypothesize that, as in mammals, recurrent neuronal activity might operate for memory retrieval in the fly olfactory system. Moreover, we present evidence for structural synaptic plasticity in the mushroom body calyx. This is the first demonstration of synaptic plasticity in the central nervous system of Drosophila melanogaster. The volume of the mushroom body calyx can change according to changes in the environment. Also size and numbers of microglomeruli - sub-structures of the calyx, at which projection neurons contact Kenyon cells - can change. We investigated the synapses within the microglomeruli in detail by using new transgenic tools for visualizing presynaptic active zones and postsynaptic densities. Here, we could show, by disruption of the projection neuron - Kenyon cell circuit, that synapses of microglomeruli were subject to activity-dependent synaptic plasticity. Projection neurons that could not generate action potentials compensated their functional limitation by increasing the number of active zones per microglomerulus. Moreover, they built more and enlarged microglomeruli. Our data provide clear evidence for an activity-induced, structural synaptic plasticity as well as for the activity-induced reorganization of the olfactory circuitry in the mushroom body calyx.}, subject = {Taufliege}, language = {en} } @phdthesis{Duechs2011, author = {D{\"u}chs, Matthias}, title = {Effects of Toll-like receptor agonists on the pathogenesis of atopic asthma in mice}, url = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-66369}, school = {Universit{\"a}t W{\"u}rzburg}, year = {2011}, abstract = {In the last decades, both the incidence and the severity of asthma have steadily increased. Furthermore, available therapies only treat the symptoms but do not cure the disease. Immune modulation induced by TLR agonists may be a promising novel approach to effectively treat asthma as it targets the underlying immunopathology directly rather than one mediator alone. The aim of this thesis was to investigate if the immunostimulatory properties of Toll-like receptor (TLR) agonists can be utilized to develop novel therapeutic intervention strategies for the treatment of asthma using murine models of allergic inflammation. For this purpose five different TLR agonists were tested in preclinical mouse models of acute and chronic asthma, both in preventive and therapeutic settings. Firstly, TLR-2, 3, 4, 7/8 and 9 agonists were delivered intratracheally at different doses before pulmonary allergen exposure in the asthma model of acute inflammation. TLR9 agonist CpG-containing oligodeoxynucleotides (CpG) > TLR7 agonist Resiquimod (R848) > TLR3 agonists poly(I:C) strongly reduced allergen induced airway eosinophilia and IL-4 levels in a dose-dependent manner. All TLR agonists increased neutrophil numbers, TLR4 agonist lipopolysaccharide (LPS) > TLR2 agonist lipoteichonic acid (LTA) > poly(I:C) > CpG > R848 and, with the exception of R848, the amount of pro-inflammatory cytokines in the airways. Suppressive effects were not dependent upon IFN-γ and IL-10 or associated with increased numbers of regulatory T cells in the airways. All TLR agonists, except LTA, similarly reduced airway eosinophilia and IL-4 levels when applied therapeutically after allergen challenge. These results show that the TLR agonists have different suppressive effects on TH2 responses in the airways which further depend on the dose and the experimental setup in which they were tested. Interestingly, all agonists induced airway neutrophilia, albeit to different degrees, raising the question if TLR ligands are safe for human use when applied directly into the lung. Different TLR agonists are also being developed for human use as adjuvants combined with allergen in specific immunotherapy. Recent clinical data suggest that this may be achieved by induction of allergen-specific TH1 responses. For this reason, the ability of different TLR agonists to induce allergen-specific TH1 and suppress allergen-specific TH2 responses in a preclinical setting was investigated in this thesis. Different doses of the TLR agonists were applied together with allergen, then mice were exposed to allergen aerosol. CpG > LPS >LTA dose-dependently strongly suppressed the development of airway eosinophilia with poly(I:C) and R848 having no effect. The decrease in eosinophilic numbers was associated withincreased neutrophils present in the airways. IL-4 and IL-5 levels in the bronchoalveolar lavage fluid were also decreased when poly(I:C), LPS, and CpG were used. All TLR agonists increased allergen-specific IgG2a, and with the exception of poly(I:C), reduced allergen-specific IgE levels in the serum. Cutaneous anaphylaxis to allergen was completely prevented when LPS or CpG were given as adjuvant. The strongest TH1 responses were induced by CpG and poly(I:C), characterized by the presence of IFN-γ in the bronchoalveolar lavage and the highest allergen-specific IgG2a levels in the serum. This data supports approaches to use TLR9 or TLR4 agonists for human therapy as adjuvant in combination with allergen in novel specific immunotherapy formulations. In the last part of the thesis, it was investigated if TLR activation can also affect the pathology of severe chronic asthma. Therapeutic administration of R848 or CpG reduced features of inflammation and remodeling. Both agonists showed superior effects to dexamethasone, with CpG being more efficient than R848. This result again supports a TLR9-based therapy as a viable option for the treatment of severe chronic asthma which may present a potential alternative for anti-inflammatory therapy with steroids. Taken together, the results of this thesis support the use of TLR agonists to treat asthma. The most favorable efficacy/safety ratio is to be expected from TLR-based therapies combining TLR4 or TLR9 agonists with allergen in specific immunotherapy. In regard to TLR agonist monotherapy, R848 and CpG showed the most promising profiles, CpG particularly in a model of severe chronic asthma. However, since all TLR agonists used in this study also showed pro-inflammatory potential, the safety aspect of such an approach needs to be taken into account.}, subject = {Toll-like Rezeptor}, language = {en} } @phdthesis{Ulrich2012, author = {Ulrich, Tanja}, title = {Function of Lin9 in vivo and MAP3K4-p38 signaling regulates p53 mediated cell cycle arrest after defective mitosis}, url = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-73975}, school = {Universit{\"a}t W{\"u}rzburg}, year = {2012}, abstract = {Eine genaue Kontrolle des Verlaufs durch die Mitose ist entscheidend f{\"u}r die Gew{\"a}hrleistung genomischer Stabilit{\"a}t und f{\"u}r die Vermeidung von Aneuploidy. Der DREAM Komplex ist ein wichtiger Regulator der Expression von mitotischen Genen. Die Depletion der DREAM-Untereinheit Lin9, f{\"u}hrt zu einer verminderten Expression von G2/M Genen und beeintr{\"a}chtigt die Proliferation. In konditionellen knockout Mauszellen (MEFs) verursacht das Ausschalten von Lin9 Defekte in Mitose und Zytokinese und l{\"o}st vorzeitige Seneszenz aus, um eine weitere Zellproliferation zu verhindern. In dieser Arbeit konnte gezeigt werden, dass der seneszente Ph{\"a}notyp in Lin9 knockout MEFs unabh{\"a}ngig von den beiden Tumorsuppressor-Signalwegen p53-p21 und p16-pRB induziert wird. Untersuchungen mit dem konditionellen Lin9 knockout Mausmodell verdeutlichten die wichtige Funktion von Lin9 in der Regulierung der mitotischen Genexpression und der Proliferation in vivo. Das Fehlen von Lin9 f{\"u}hrte zu einer verringerten Proliferation in den Krypten des D{\"u}nndarms und verursachte eine Atrophie des Darmepithels und einen schnell eintretenden Tod der Tiere. Im zweiten Teil der Arbeit wurden Signalwege untersucht, die nach fehlerhafter Zytokinese zu einem p53 vermittelten G1-Arrest f{\"u}hren. Hierf{\"u}r wurde ein chemischer Inhibitor der mitotischen Kinase Aurora B verwendet. Mit Hilfe eines Hochdurchsatz siRNA Screens wurde die MAP Kinase MAP3K4 als Aktivator des p53 Signalwegs identifiziert. Es konnte gezeigt werden, dass MAP3K4 die Stresskinase p38b aktiviert, um den p53 vermittelten Zellzyklusarrest in tetraploiden Zellen auszul{\"o}sen. Dabei wurde p38b nach Hemmung von Aurora B f{\"u}r die transkriptionelle Aktivierung des p53 Zielgens p21 ben{\"o}tigt. Im Gegenteil dazu erfolgte die Phosphorylierung, Stabilisierung und die Rekrutierung von p53 an den p21 Promoter unabh{\"a}ngig von p38. Die teilweise Hemmung von Aurora B zeigte, dass fehlerhafte Segregation von Chromosomen auch den MAP3K4-p38-p53 Signalweg aktiviert und l{\"a}sst darauf schließen, dass subtile Defekte in der Mitose ausreichen diesen Stress-Signalweg zu induzieren. Obwohl p38 f{\"u}r den G1 Zellzyklusarrest nach mitotischen Sch{\"a}den erforderlich war, f{\"u}hrte die gleichzeitige Inhibierung von p38 und Aurora B {\"u}ber einen l{\"a}ngeren Zeitraum zu einer verringerten Proliferation, vermutlich aufgrund verst{\"a}rkter Apoptose. Es ist anzunehmen, dass der MAP3K4-p38-p53 Signalweg generell nach Defekten in der Mitose oder Zytokinese aktiviert wird um Zellen in G1 zu arretieren und um chromosomale Instabilit{\"a}t zu vermeiden.}, subject = {Mitose}, language = {en} } @phdthesis{Hsieh2011, author = {Hsieh, Samuel Yu-Lung}, title = {The diversity and ecology of the spider communities of European beech canopy}, url = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-66966}, school = {Universit{\"a}t W{\"u}rzburg}, year = {2011}, abstract = {Ein wesentliches Ziel {\"o}kologischer Forschung ist es, die Frage zu beantworten, wie Arten koexistieren k{\"o}nnen und die biologische Vielfalt erhalten bleibt. Um zu verstehen, wie dabei Gemeinschaften in unterschiedlichen r{\"a}umlich-zeitlichen Dimensionen interagieren, um die biologische Vielfalt zu erhalten, ist ein umfassendes prozessorientiertes Wissen erforderlich. Demzufolge konzentrierte sich meine Studie im Wesentlichen auf die Biodiversit{\"a}t und die sie beeinflussenden raum-zeitlichen {\"o}kologischen Prozesse. Vergleicht man die {\"A}hnlich- bzw. Un{\"a}hnlichkeit der in verschieden alten Best{\"a}nden lebenden Spinnengemeinschaften der Buchen (Fagus sylvatica L.), dann zeigt sich, dass die {\"a}lteste Baumkohorte offensichtlich einzigartige Ressourcen besitzt, welche die Zusammensetzung der Spinnengemeinschaften deutlich pr{\"a}gen. {\"U}ber das Jahr hin zeigten die Spinnengemeinschaften trotz der jahreszeitlich unterschiedlich {\"o}kologischen Randbedingungen eine sich wiederholende, vorhersehbare Dynamik. Der Vergleich {\"u}ber die Jahre ergab, dass das "Neutrale Modell" und das "Nischen-Modell" gleichzeitig funktionieren k{\"o}nnen. Beide sind notwendig, um die Dynamik der in den Buchenkronen der verschiedenen Altersklassen lebenden Spinnengemeinschaften vollst{\"a}ndig erkl{\"a}ren zu k{\"o}nnen.}, subject = {Spinnen}, language = {en} } @phdthesis{Schul2013, author = {Schul, Daniela}, title = {Spatio-temporal investigation and quantitative analysis of the BMP signaling pathway}, url = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-84224}, school = {Universit{\"a}t W{\"u}rzburg}, year = {2013}, abstract = {Bone Morphogenetic Proteins (BMPs) are key regulators for a lot of diverse cellular processes. During embryonic development these proteins act as morphogens and play a crucial role particularly in organogenesis. BMPs have a direct impact on distinct cellular fates by means of concentration-gradients in the developing embryos. Using the diverse signaling input information within the embryo due to the gradient, the cells transduce the varying extracellular information into distinct gene expression profiles and cell fate decisions. Furthermore, BMP proteins bear important functions in adult organisms like tissue homeostasis or regeneration. In contrast to TGF-ß signaling, currently only little is known about how cells decode and quantify incoming BMP signals. There is poor knowledge about the quantitative relationships between signal input, transducing molecules, their states and location, and finally their ability to incorporate graded systemic inputs and produce qualitative responses. A key requirement for efficient pathway modulation is the complete comprehension of this signaling network on a quantitative level as the BMP signaling pathway, just like many other signaling pathways, is a major target for medicative interference. I therefore at first studied the subcellular distribution of Smad1, which is the main signal transducing protein of the BMP signaling pathway, in a quantitative manner and in response to various types and levels of stimuli in murine c2c12 cells. Results indicate that the subcellular localization of Smad1 is not dependent on the initial BMP input. Surprisingly, only the phospho-Smad1 level is proportionally associated to ligand concentration. Furthermore, the activated transducer proteins were entirely located in the nucleus. Besides the subcellular localization of Smad1, I have analyzed the gene expression profile induced by BMP signaling. Therefore, I examined two endogenous immediate early BMP targets as well as the expression of the stably transgenic Gaussia Luciferase. Interestingly, the results of these independent experimental setups and read-outs suggest oscillating target gene expression. The amplitudes of the oscillations showed a precise concentration-dependence for continuous and transient stimulation. Additionally, even short-time stimulation of 15' activates oscillating gene-expression pulses that are detectable for at least 30h post-stimulation. Only treatment with a BMP type I receptor kinase inhibitor leads to the complete abolishment of the target gene expression. This indicated that target gene expression oscillations depend directly on BMP type I receptor kinase activity.}, subject = {Knochen-Morphogenese-Proteine}, language = {en} } @article{BirkmayerSebaldBuecher1969, author = {Birkmayer, G. D. and Sebald, Walter and B{\"u}cher, Th.}, title = {Cytochrom-Oxydase und ein an diese assoziiertes, markiertes Protein aus 14C-markierten Mitochondrien von Neurospora crassa}, url = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-82135}, year = {1969}, abstract = {no abstract available}, subject = {Physiologische Chemie}, language = {de} } @article{SchwabSebaldWeiss1972, author = {Schwab, A. J. and Sebald, Walter and Weiss, H.}, title = {Schnelle Markierung eines mitochondrial synthetisiertem Polypeptids einer Cytochromoxidasen-Pr{\"a}paration aus Neurospora}, url = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-84206}, year = {1972}, abstract = {no abstracts available}, subject = {Physiologische Chemie}, language = {de} } @article{SebaldWeissJackl1972, author = {Sebald, Walter and Weiss, H. and Jackl, G.}, title = {{\"U}ber die Abh{\"a}ngigkeit des Zusammenbaus der Cytochromoxidase von der Anwesenheit der Produkte der mitochondrialen Proteinsynthese}, url = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-84192}, year = {1972}, abstract = {no abstract available}, subject = {Physiologische Chemie}, language = {de} } @article{JacklSebald1974, author = {Jackl, G. and Sebald, Walter}, title = {Identification of two products of mitochondrial protein synthesis associated with oligomycin-sensitive ATPase from Neurospora crassa}, url = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-82093}, year = {1974}, abstract = {no abstract available}, subject = {Physiologische Chemie}, language = {en} } @article{WeissSebald1978, author = {Weiss, H. and Sebald, Walter}, title = {Purification of cytochrome oxidase from Neurospora crassa and other sources}, url = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-82082}, year = {1978}, abstract = {A chromatographic procedure 1 is described by means of which cytochrome oxidase has been purified from a variety of organisms including the fungus N eurospora crassa,2,3 the unicellular alga Po/ytoma mirum, 4 the insect Locusta migratoria ,5 the frog Xenopus muel/eri,4 and the mammal Rattus norwegicus. 4 This procedure can be used to equal effect for large-scale preparations, starting from grams of mitochondrial protein, or for small-scale preparations starting from milligrams. The cytochrome oxidase preparations from the different organisms are enzymically active. They show similar subunit compositions.}, subject = {Biochemie}, language = {en} } @article{SebaldNeupertWeiss1979, author = {Sebald, Walter and Neupert, W. and Weiss, H.}, title = {Preparation of Neurospora crassa mitochondria}, url = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-82070}, year = {1979}, abstract = {The fungus Neurospora crassa represents a eukaryotic cell with high biosynthetic activities. Cell mass doubles in 2-4 hr during expone ntial growth , even in simple salt media with sucrose as the sole carbon source. The microorgani sm forms a mycelium of long hyphae durlng vegetative growth . The mitochondria can be isolated under relatively gentle condi tions since a few breaks in the threadlike hyphae are sufficient to cause the outflow of the organelles. This article describes two methods for the physical disruption of the hyphae : (I) The cell s are opened in a grind mill between two rotating corundum di sks. This is a continuous and fast procedure and allows large- and small-scale preparations of mitochondria. (2) Hyphae are ground with sand in a mortar and pestle. This procedure can be applied to microscale preparations of mitochondria starting with minute amounts of cells. Other procedures for the isolation of Neurospora mitochondria after the physical di sruption or the enzymatic degradation of the cell wall have been described elsewhere}, subject = {Biochemie}, language = {en} } @article{SebaldWild1979, author = {Sebald, Walter and Wild, G.}, title = {Mitochondrial ATPase complex from Neurospora crassa}, url = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-82065}, year = {1979}, abstract = {The A TPase eomplex has been isolated from mitoehondria of N eurospora crassa by immunologieal teehniques. The protein ean be obtained rapidly and qua ntitatively in high purity by miero- or large-seale immunopreeipitation. Immunopreeipitation has been applied to labeled and doubly labeled mitoehondrial proteins in order to investigate the number and moleeular weights of subunit polypeptides , the site of synthesis of subunit polypeptides, and the dieycIohexyIcarbodiimide-binding protein . The A TPase complex obtained by large-seale immunopreeipitation has been used as starting ma terial for the isolation of hydrophobie polypeptides.}, subject = {Biochemie}, language = {en} } @article{SebaldWernerWeiss1979, author = {Sebald, Walter and Werner, S and Weiss, H}, title = {Biogenesis of mitochondrial membrane proteins in Neurospora crassa}, url = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-82055}, year = {1979}, abstract = {no abstract available}, subject = {Biochemie}, language = {en} } @article{WernerSebald1981, author = {Werner, S. and Sebald, Werner}, title = {Immunological techniques for studies on the biogenesis of mitochondrial membrane proteins}, url = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-82044}, year = {1981}, abstract = {no abstract available}, subject = {Biochemie}, language = {en} } @article{ViebrockPerzSebald1983, author = {Viebrock, A and Perz, A and Sebald, Walter}, title = {Molecular cloning of middle-abundant mRNAs from Neurospora crassa}, url = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-82033}, year = {1983}, abstract = {no abstract available}, subject = {Neurospora crassa}, language = {en} } @article{HoppeSebald1984, author = {Hoppe, J. and Sebald, Walter}, title = {The proton conducting F0-part of bacterial ATP synthases}, url = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-82019}, year = {1984}, abstract = {No abstract available}, subject = {Biologie}, language = {en} } @phdthesis{Bruder2012, author = {Bruder, Jessica}, title = {Antigenerkennung bei autoaggressiven Lymphozyten}, url = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-73342}, school = {Universit{\"a}t W{\"u}rzburg}, year = {2012}, abstract = {Millionen Menschen weltweit leiden an den verschiedensten Autoimmunerkrankungen. Diese Krankheiten entstehen, wenn das Immunsystem gesundes k{\"o}rpereigenes Gewebe angreift und zerst{\"o}rt. An der Pathogenese sind sowohl Komponenten des angeborenen Immunsystems als auch Bestandteile des adaptiven Immunsystems, wie Lymphozyten und Antik{\"o}rper, beteiligt. Da die Ursachen und molekularen Mechanismen der Pathogenese dieser Erkrankungen bis heute weitgehend unbekannt sind, wurden in dieser Arbeit autoaggressive Lymphozyten bei den humanen Autoimmunerkrankungen Polymyositis und Multiple Sklerose n{\"a}her untersucht. Die Polymyositis ist eine chronisch entz{\"u}ndliche Erkrankung der Skelettmuskulatur. Die Muskelfasern werden dabei von zytotoxischen CD8+ gd-T-Lymphozyten infiltriert, attackiert und schließlich zerst{\"o}rt. In einem seltenen Fall der Polymyositis wurden die Muskelzellen hingegen in {\"a}hnlicher Weise von CD8- gd-T-Lymphozyten angegriffen. Die gd-T-Lymphozyten waren monoklonal expandiert und ihr Rezeptor, im Folgenden als M88 bezeichnet, wurde als Vg1.3+Vd2+ identifiziert. Fr{\"u}here Untersuchungen der Antigenspezifit{\"a}t dieser Zellen zeigten, dass M88 mehrere funktionell und strukturell verschiedene Proteine aus unterschiedlichen Spezies erkennt. Die Bindung erfolgt spezifisch durch die Antigenerkennungsregionen beider Rezeptorketten von M88. In dieser Arbeit wurden verschiedene bakterielle und humane Proteine des Translationsapparates als Antigene von M88 identifiziert. Weitere ausf{\"u}hrliche Untersuchungen eines paradigmatischen bakteriellen Antigens, dem Translationsinitiationsfaktor EcIF1, zeigten, dass M88 an Oberfl{\"a}chen-exponierte Konformationsepitope von Proteinen bindet. Interessanterweise erkennt M88 mehrere humane Aminoacyl-tRNA-Synthetasen, Antigene, die in anderen Formen der Myositis von Autoantik{\"o}rpern angegriffen werden. Diese Beobachtung ergibt eine bemerkenswerte Verbindung zwischen T-Zell- und Antik{\"o}rper-vermittelten B-Zell-Antworten bei der autoimmunen Myositis. Bei der Multiplen Sklerose ist das zentrale Nervensystem betroffen. Autoaggressive Lymphozyten greifen die Myelinschicht der Nervenzellen im Gehirn und R{\"u}ckenmark an und zerst{\"o}ren sie. Im Liquor cerebrospinalis von Patienten lassen sich klonal expandierte und affinit{\"a}tsgereifte B-Zellen sowie „oligoklonale Banden" (OKB) Antik{\"o}rper nachweisen. Obwohl diese Merkmale auf eine Antigen-induzierte Immunantwort hindeuten, sind die zugrundeliegenden Antigene und die Rolle der OKB bei der Pathogenese bis heute unbekannt. In dieser Arbeit wurde die Antigenspezifit{\"a}t von f{\"u}nf IgG OKB-Antik{\"o}rpern aus drei Patienten untersucht. Durch verschiedene proteinbiochemische Methoden konnten intrazellul{\"a}re Kandidatenantigene identifiziert werden. Interessanterweise sind darunter mehrere nukle{\"a}re Proteine, die an der Transkriptionsregulation oder der RNA-Prozessierung beteiligt sind. Reaktivit{\"a}ten gegen intrazellul{\"a}re Antigene treten auch bei anderen Autoimmunerkrankungen, wie beispielsweise dem systemischen Lupus erythematodes, auf. Diese Ergebnisse k{\"o}nnten auf einen allgemeinen Mechanismus der Entstehung und Funktion von Autoantik{\"o}rpern bei diesen humanen Autoimmunerkrankungen hindeuten.}, subject = {Multiple Sklerose}, language = {de} }