TY - JOUR A1 - Nanguneri, Siddharth A1 - Flottmann, Benjamin A1 - Horstmann, Heinz A1 - Heilemann, Mike A1 - Kuner, Thomas T1 - Three-Dimensional, Tomographic Super-Resolution Fluorescence Imaging of Serially Sectioned Thick Samples JF - PLoS One N2 - Three-dimensional fluorescence imaging of thick tissue samples with near-molecular resolution remains a fundamental challenge in the life sciences. To tackle this, we developed tomoSTORM, an approach combining single-molecule localization-based super-resolution microscopy with array tomography of structurally intact brain tissue. Consecutive sections organized in a ribbon were serially imaged with a lateral resolution of 28 nm and an axial resolution of 40 nm in tissue volumes of up to 50 \(\mu\)mx50\(\mu\)mx2.5\(\mu\)m. Using targeted expression of membrane bound (m)GFP and immunohistochemistry at the calyx of Held, a model synapse for central glutamatergic neurotransmission, we delineated the course of the membrane and fine-structure of mitochondria. This method allows multiplexed super-resolution imaging in large tissue volumes with a resolution three orders of magnitude better than confocal microscopy. KW - architecture KW - rat calyx KW - in-vivo KW - microscopy KW - resolution KW - proteins KW - transmission KW - ultrastructure KW - reconstruction KW - localization Y1 - 2012 U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-134434 VL - 7 IS - 5 ER - TY - JOUR A1 - Aso, Yoshinori A1 - Herb, Andrea A1 - Ogueta, Maite A1 - Siwanowicz, Igor A1 - Templier, Thomas A1 - Friedrich, Anja B. A1 - Ito, Kei A1 - Scholz, Henrike A1 - Tanimoto, Hiromu T1 - Three Dopamine Pathways Induce Aversive Odor Memories with Different Stability JF - PLoS Genetics N2 - Animals acquire predictive values of sensory stimuli through reinforcement. In the brain of Drosophila melanogaster, activation of two types of dopamine neurons in the PAM and PPL1 clusters has been shown to induce aversive odor memory. Here, we identified the third cell type and characterized aversive memories induced by these dopamine neurons. These three dopamine pathways all project to the mushroom body but terminate in the spatially segregated subdomains. To understand the functional difference of these dopamine pathways in electric shock reinforcement, we blocked each one of them during memory acquisition. We found that all three pathways partially contribute to electric shock memory. Notably, the memories mediated by these neurons differed in temporal stability. Furthermore, combinatorial activation of two of these pathways revealed significant interaction of individual memory components rather than their simple summation. These results cast light on a cellular mechanism by which a noxious event induces different dopamine signals to a single brain structure to synthesize an aversive memory. KW - dynamics KW - serotonin KW - expression KW - melanogaster KW - neurons form KW - olfactory memory KW - long-term-memory KW - drosophila mushroom body KW - sensitization KW - localization Y1 - 2012 U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-130631 VL - 8 IS - 7 ER - TY - JOUR A1 - Kühn, Heike A1 - Schön, Franz A1 - Edelmann, Karola A1 - Brill, Stefan A1 - Müller, Joachim T1 - The Development of Lateralization Abilities in Children with Bilateral Cochlear Implants JF - ORL N2 - Objectives: The purpose of this study was to investigate the development of lateralization skills in children who received bilateral cochlear implants (CIs) in sequential operations. Methods: The lateralization skills of 9 children with a mean age of 4.1 years at the first surgery and 5.5 years at the second surgery were assessed at 3 time intervals. Children were assessed with a 3-loudspeaker setup (front, left and right) at 0.9 years (interval I) and 1.6 years (interval II) after the second implantation, and after 5.3 years of bilateral implant use (interval III) with a 9-loudspeaker setup in the frontal horizontal plane between -90° and 90° azimuth. Results: With bilateral implants, a significant decrease in lateralization error was noted between test interval I (45.0°) and II (23.3°), with a subsequent significant decrease at test interval III (4.7°). Unilateral performance with the CI did not improve significantly between the first 2 intervals; however, there was a bias of responses towards the unilateral side by test interval III. Conclusions: The lateralization abilities of children with bilateral CIs develop in a relatively short period of time (1-2 years) after the second implant. Children appear to be able to acquire binaural skills after bilateral cochlear implantation. KW - localization KW - bilateral cochlear implant KW - children KW - MED-EL cochlear implant KW - lateralization Y1 - 2013 U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-196375 SN - 0301-1569 SN - 1423-0275 N1 - This publication is with permission of the rights owner freely accessible due to an Alliance licence and a national licence (funded by the DFG, German Research Foundation) respectively. VL - 75 IS - 2 ER - TY - THES A1 - Wennmann, Andreas T1 - Retrospektiver Vergleich der präoperativen Lokalisationsdiagnostik mit der intraoperativen Detektion von Nebenschilddrüsen-Adenomen sowie dem perioperativen Verlauf bei Patienten/Patientinnen mit primärem Hyperparathyreoidismus T1 - Retrospective comparison of preoperative localization diagnostics with intraoperative detection of parythyroid adenomas as well as perioperative course in patients with primary hyperparathyroidism N2 - Die Exstirpation erkrankter Nebenschilddrüsen (NSD) ist die einzige kurative Therapie des primären Hyperparathyreoidismus (pHPT). Die präoperative Detektion der dem pHPT zugrunde liegenden NSD-Adenome durch eine adäquate Lokalisationsdiagnostik stellt eine wichtige Säule bei der Operationsplanung dar. Angesichts der umfangreichen diagnostischen Möglichkeiten ist noch nicht abschließend beantwortet, wie viel und welche Diagnostik mit hoher Wahrscheinlichkeit zur erfolgreichen Lokalisation von NSD-Adenomen führt und ob/wie diese den perioperativen Verlauf beeinflusst. Die Beantwortung dieser Fragen war das Hauptziel der vorliegenden Arbeit. Es handelt sich um eine monozentrische, retrospektive Datenanalyse anhand des Kollektivs des Universitätsklinikums Würzburg (UKW) der Jahre 2005 bis 2017. Nach Datenextraktion aller Patienten/Patientinnen mit Hyperparathyreoidismus aus dem Dokumentationssystem des UKW erfolgten die deskriptiven und statistischen Auswertungen mittels Excel und SPSS. Insgesamt wurden im untersuchten Zeitraum 467 Patienten/Patientinnen aufgrund eines pHPT operiert. NSD-Sono und NSD-Szinti waren die am häufigsten durchgeführten Lokalisationsdiagnostika mit Sensitivitäten von 61,5 % bzw. 66,3 % für die Seite. Bei der Etagen-Blutentnahme lag die Sensitivität bei 100 %; bei der MRT bei 47,4 % und bei der 11Kohlenstoff-Methionin-Positronenemissionstomographie/Computertomographie (11C-Methionin-PET/CT) bei 58,8 %. Durch zusätzliche Diagnostik konnte nicht grundsätzlich eine Erhöhung der Treffsicherheit erreicht werden. Die Analyse der perioperativen Parameter zeigte, dass das Alter der Operierten positiv mit der Operationsdauer, der Krankenhausaufenthaltsdauer und dem Auftreten postoperativer Hypocalcämien korrelierte. Die Einnahme eines Thrombozytenaggregationshemmers führte zu einer verlängerten Krankenhausaufenthaltsdauer. Die therapeutische Antikoagulation war ein Risikofaktor in Bezug auf längere OP-Dauern und das Auftreten von Nachblutungen. Eine zusätzlich zur Parathyreoidektomie durchgeführte Sanierung der Schilddrüse war mit einer erhöhten Rate an postoperativen Hypocalcämien vergesellschaftet. Zusammenfassend zeigen die vorliegenden Daten, dass nach initial vermeintlich erfolgreicher Detektion eines NSD-Adenoms mit NSD-Sono oder NSD-Szinti eine weiterführende Lokalisationsdiagnostik nicht sinnvoll ist. Nach initial erfolgloser NSD-Sono oder NSD-Szinti dagegen ist die Durchführung einer 11C-Methionin-PET/CT zu erwägen. N2 - Extirpation of diseased parathyroid glands is the only curative therapy for primary hyperparathyroidism (pHPT). Preoperative localization of parathyroid adenomas underlying pHPT by appropriate localization diagnostics is important for planning surgery. Considering extensive diagnostic possibilities, it is not completely clear yet how much and which diagnostics with high probability will detect parathyroid adenomas correctly and if/how it influences perioperative course. Answering these questions was main aim of the present work. It is a monocentric, retrospective data analysis of the collective of Universitätsklinikum Würzburg (UKW) from 2005 - 2017. After data extraction of all patients with hyperparathyroidism out of documentation system of UKW, descriptive and statistic evaluations were made by Excel and SPSS. All in all, 467 patients underwent surgery for pHPT during the investigated timespace. Parathyroid-ultrasound and parathyroid-scintigraphy were the localization techniques used most frequently with sensitivities of 61,5 % and 66,3 % respectively for correct localization of the side. Sensitivity of selective venous sampling was 100 %, of MRI was 47,4 % and of 11carbon methionine positron emission tomography/computed tomography (11C methionine PET/CT) was 58,8 %. Using additional diagnostics, the detection rate could not necessarily be increased. Analysis of perioperative parameters showed that age was positively correlated with duration of surgery, length of stay at the hospital and postoperative hypocalcaemias. Inhibitors of platelet aggregation led to longer duration of hospitalisation stay. Therapeutic anticoagulation was risk factor for longer duration of surgery and appearance of postoperative bleedings. Additional to parathyroid gland performed thyroid surgery was associated with postoperative hypocalcaemias. In summary the present data show that after supposedly successful parathyroid ultrasound or parathyroid scintigraphy, no further localization diagnostics is indicated. After initially unsuccessful parathyroid ultrasound or parathyroid scintigraphy however, 11C methionine PET/CT should be considered. KW - Primärer Hyperparathyreoidismus KW - Epithelkörperchen KW - Lokalisation KW - Operation KW - Verlauf KW - primary hyperparathyroidism KW - parathyroid glands KW - localization KW - surgery KW - course Y1 - 2021 U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-249895 ER - TY - JOUR A1 - Kaiser, Bettina A1 - Vogg, Gerd A1 - Fürst, Ursula B. A1 - Albert, Markus T1 - Parasitic plants of the genus Cuscuta and their interaction with susceptible and resistant host plants JF - Frontiers in Plant Science N2 - By comparison with plant microbe interaction, little is known about the interaction of parasitic plants with their hosts. Plants of the genus Cuscuta belong to the family of Cuscutaceae and comprise about 200 species, all of which live as stem holoparasites on other plants. Cuscuta spp. possess no roots nor fully expanded leaves and the vegetative portion appears to be a stem only. The parasite winds around plants and penetrates the host stems via haustoria, forming direct connections to the vascular bundles of their hosts to withdraw water, carbohydrates, and other solutes. Besides susceptible hosts, a few plants exist that exhibit an active resistance against infestation by Cuscuta spp. For example, cultivated tomato (Solanum lycopersicum) fends off Cuscuta reflexa by means of a hypersensitive-type response occurring in the early penetration phase. This report on the plant plant dialog between Cuscuta spp. and its host plants focuses on the incompatible interaction of C. reflexa with tomato. KW - incompatible interaction KW - messenger-RNA KW - Reflexa Roxb KW - localization KW - symbiosis KW - parasitic plants KW - plant-plant interaction KW - Cuscuta KW - dodder KW - plant immunity KW - resistance KW - Lycopersicon esculentum KW - phenolic constituents KW - Orobanche crenata KW - weed dodder KW - tomato KW - striga Y1 - 2015 U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-144091 VL - 6 IS - 45 ER - TY - THES A1 - Stürmer, Andrea T1 - Interaktionen und Lokalisationen der Replikationsproteine der Maus T1 - Interactions and Localizations of murine Replication Proteins N2 - Die Initiation der DNA-Replikation in Eukaryonten ist ein hochkonservierter Prozess, der in drei Stufen unterteilt werden kann. Im ersten Schritt bindet der „origin recognition complex“ (ORC) an Replikationsorigins innerhalb chromosomaler DNA, wodurch eine Assemblierung des präreplikativen Komplexes an diesen Startpunkten ausgelöst wird. An den ORC lagern sich anschließend die Proteine CDC6 und RLF-B/CDT1 an, die beide schließlich für die Rekrutierung des heterohexameren MCM-Komplexes verantwortlich sind. Durch die Aktivität der Kinase CDC7/DBF4 wird der Origin für den Start der DNA-Replikation lizenziert, sobald die finale Anlagerung des Initiationsfaktors CDC45 den präreplikativen Komplex vervollständigt hat. Ein Ziel der vorliegenden Arbeit war es, das komplexe Netzwerk von Protein-Protein-Interaktionen zwischen den verschiedenen Initiationsfaktoren durch FRET-Studien aufzuklären. Es konnten Interaktionen zwischen MCM5 und MCM3, MCM5 und MCM7, ORC5 und MCM7, sowie CDT1 und MCM6 in vivo nachgewiesen werden. Die vorliegende Arbeit hatte weiterhin die Untersuchung der intrazellulären Lokalisation der sechs murinen MCM-Proteine in Fibroblasten-Zellen der Maus zum Ziel.Lokalisationsstudien der EGFP-gekoppelten MCM-Proteine zeigten, dass die Proteine EGFP-MCM4, MCM4-EGFP, MCM4-NLS-EGFP, EGFP-MCM5, MCM5-EGFP, MCM5-NLS-EGFP, und EGFP-MCM7 u.a. am Centrosom lokalisiert sind. Durch Immunfluoreszenz-Färbung mit Antikörpern gegen eine konservierte Domäne aller sechs MCM-Untereinheiten sowie mit spezifischen MCM3- und MCM6-Antikörpern konnte eine centrosomale Lokalisation auch für die endogenen Proteine nachgewiesen werden. Zusätzlich zu den Lokalisationsanalysen konnte über Immunpräzipitationsstudien gezeigt werden, dass MCM3 und MCM6 mit dem centrosomalen Protein g-Tubulin präzipitierbar sind. Die Tatsache, dass alle Untereinheiten des MCM-Komplexes mit dem Centrosom assoziiert sind, deutet darauf hin, dass die MCM-Proteine am Centrosom als Multiproteinkomplex gebunden sind. Da MCM3 und MCM6 auch in allen Mitose-Stadien an das Centrosom gebunden sind, kann von einer funktionellen Aufgabe dieser Proteine während der Zellteilung ausgegangen werden. Im letzten Teil dieser Arbeit sollte die Funktion der MCM-Proteine am Centrosom durch „knock-down“ des Proteins MCM3 mittels RNA-Interferenz-Studien untersucht werden. Ziel war, ein induzierbares MCM3-siRNA-exprimierendes System zu etablieren. Das gezielte An- und Abschalten der MCM3siRNA-Transkription sollte durch das TetOn-System ermöglicht werden. Bei diesem System wird durch Zugabe von Doxycyclin die Transkription aktiviert, bei Abwesenheit von Doxycyclin wird sie abgeschaltet. Auf dieser Basis wurde der Einfluss von Doxycyclin auf das Wachstumsverhalten der MCM3siRNA-exprimierenden Zelllinie untersucht. Im Vergleich zu NIH/3T3-Zellen und NIH/3T3-TetOn-Zellen konnte eine deutlich reduzierte Proliferation bei Behandlung der Zellen mit Doxycyclin beobachtet werden. Diese Ergebnisse deuten auf eine durch Produktion von MCM3siRNA verursachte Störung des Zellwachstums hin. Zusätzlich beeinflusst die durch Doxycyclin induzierte Synthese von MCM3siRNA die Zellzyklusverteilung. So befinden sich nach Doxycyclinbehandlung mehr Zellen in der G2/M-Phase als in unbehandelten, asynchronen NIH/3T3-Zellen. Die MCM3-Proteinmenge wurde nach 19 Tagen Doxycyclinbehandlung fast vollständig durch die produzierte MCM3siRNA herunterreguliert. Um einen möglichen Einfluss der MCM3siRNA auf andere MCM-Proteine zu untersuchen, wurde der Protein-Level von MCM6 analysiert. Dabei wurde eine vermehrte MCM6-Expression nachgewiesen. Diese Beobachtung deutet darauf hin, dass durch Bildung von MCM3siRNA der Expressions-Level von MCM6 beeinflusst wird. Auffällig häufig lagen in MCM3-„knock-down“-Zellen mehrere Zellkerne vor. Neben Zellen mit zwei Zellkernen finden sich auch Zellen mit einer ungeraden Anzahl an Zellkernen. Demnach durchlaufen die Zellkerne in einer Zelle unterschiedliche Zellzyklusstadien. Die Phänotypen, die nach Transkription der MCM3siRNA beobachtet wurden, sind komplex und zeigen Defekte in zahlreichen Mitose-Stadien. Das Auftreten multinukleärer Zellen ist auf eine fehlende Cytokinese zurückzuführen. Die Mikrotubuli waren in den MCM3-„knock-down“-Zellen nur unzureichend organisiert, wobei sie kaum mit der Zellperipherie verankert waren. Diese Resultate weisen darauf hin, dass die MCM-Proteine neben ihrer essentiellen Rolle in der Ausbildung des präreplikativen Komplexes eine zusätzliche Funktion in der Mitose ausüben. N2 - The initiation of DNA replication is a highly conserved process which is subdivided into three steps. The first step is the binding of the “origin recognition complex” (ORC) to the replication origins in chromosomal DNA which triggers the assembly of the prereplicative complex at the origins. Subsequently the proteins CDC6 and the RLF-B/CDT1 bind to ORC which are both responsible for the recruitment of the heterohexameric MCM-complex to the prereplicative complex (preRC). The kinase CDC7/DBF4 licenses the origin after completion of the preRC by binding of the CDC45 protein. One task of this work was to dissolve the complex network of protein-protein interactions between the different initiator proteins using the method of FRET (Fluorescence Resonance Energy Transfer). Interactions were found between MCM5 and MCM3, MCM5 and MCM7, ORC5 and MCM7 as well as between CDT1 and MCM6. A further task of this work was to study the intracellular localization of the six murine MCM proteins in murine fibroblasts.In a MCM2-EGFP expressing cell population multinucleated cells occurred frequently. This indicates an incorrect cell division caused by overexpression of MCM2-EGFP and to a possible role of MCM2 in mitosis. Inspecting the intracellular localization of EGFP-fused MCM-proteins was shown, that EGFP-MCM4, MCM4-EGFP, MCM4-NLS-EGFP, EGFP-MCM5, MCM5-EGFP, MCM5-NLS-EGFP, and EGFP-MCM7 were localized in the centrosomes. In contrast, the proteins MCM2-EGFP, EGFP-MCM2, MCM3-EGFP, EGFP-MCM3, MCM6-EGFP, MCM6-NLS-EGFP, MCM7-EGFP and MCM7-NLS-EGFP are not associated with centrosomes. The localization of endogeneous MCM proteins was analyzed by immunostaining using antibodies against a conserved region among all MCM proteins and also with specific antibodies against MCM3 and MCM6. Centrosomal localization was observed for the MCM proteins and in particular for MCM3 and MCM6. In addition to localization studies, immunoprecipitations showed that MCM3 and MCM6 precipitate with the centrosomal protein g-tubulin. The fact that all MCM proteins assemble at the centrosome, indicates that the MCM proteins act as a multiprotein complex at the centrosome. Since MCM3 and MCM6 are bound to centrosomes in all stages of mitosis these proteins may play a role in the progression of cell division. In the last part of this work, the function of MCM3 at the centrosome was analyzed by protein knock-down using the method of RNA interference. To approach this, an inducible MCM3siRNA-expressing system was established. Switching the transcription of MCM3siRNA on and off was made feasible using the TetOn-System. In this system the transcription is activated by addition of doxycycline, without doxycycline the transcription is switched-off. The influence of doxycycline on cell growth of the MCM3siRNA-expressing cell line was analyzed. By comparison to NIH/3T3 cells and NIH/3T3-TetOn cells a significantly reduced proliferation rate was observed after treatment with doxycycline. These results suggest a disturbance of cell growth by MCM3siRNA production. After treatment with doxycycline more cells are accumulated in G2/M phase compared to untreated cells. The expression of MCM3 was almost completely knocked-down by treatment of cells with doxycycline for 19 days. To analyze the influence of MCM3siRNA on other MCM proteins, the protein level of MCM6 was examined. An increased MCM6 expression was observed. This implies that MCM3siRNA influences the expression level of MCM6. More nuclei were frequently observed in MCM3 knocked-down cells. Cells with two nuclei as well as cells with an impaired number of nuclei were observed, indicating that probably the nuclei pass thruogh different cell cycle stages. Phenotypes observed after expression of MCM3siRNA showed defects in multiple stages of mitosis. The presence of multinucleated cells is apparently due to a blocked cytokinesis. Microtubuli were insufficiently organized and were deficiently bound to the cellular periphery. These results indicate an essential role of the MCM proteins in mitosis besides its described role in the establishment of the prereplicative complex. KW - Replikation KW - Maus KW - Proteine KW - Interaktion KW - Replikation KW - Lokalisation KW - Interaktion KW - Proteine KW - replication KW - localization KW - interaction KW - proteins Y1 - 2004 U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-9563 ER - TY - JOUR A1 - Fagan, Jeremy K. A1 - Dollar, Gretchen A1 - Lu, Qiuheng A1 - Barnett, Austen A1 - Jorge, Joaquin Pechuan A1 - Schlosser, Andreas A1 - Pfleger, Cathie A1 - Adler, Paul A1 - Jenny, Andreas T1 - Combover/CG10732, a Novel PCP Effector for Drosophila Wing Hair Formation JF - PLOS ONE N2 - The polarization of cells is essential for the proper functioning of most organs. Planar Cell Polarity (PCP), the polarization within the plane of an epithelium, is perpendicular to apical-basal polarity and established by the non-canonical Wnt/Fz-PCP signaling pathway. Within each tissue, downstream PCP effectors link the signal to tissue specific readouts such as stereocilia orientation in the inner ear and hair follicle orientation in vertebrates or the polarization of ommatidia and wing hairs in Drosophila melanogaster. Specific PCP effectors in the wing such as Multiple wing hairs (Mwh) and Rho Kinase (Rok) are required to position the hair at the correct position and to prevent ectopic actin hairs. In a genome-wide screen in vitro, we identified Combover (Cmb)/CG10732 as a novel Rho kinase substrate. Overexpression of Cmb causes the formation of a multiple hair cell phenotype (MHC), similar to loss of rok and mwh. This MHC phenotype is dominantly enhanced by removal of rok or of other members of the PCP effector gene family. Furthermore, we show that Cmb physically interacts with Mwh, and cmb null mutants suppress the MHC phenotype of mwh alleles. Our data indicate that Cmb is a novel PCP effector that promotes to wing hair formation, a function that is antagonized by Mwh. KW - planar cell polarity KW - RHO-associated kinease KW - convergent extension movements KW - ROK-alpha KW - protein KW - phosphorylation KW - actin KW - gene KW - morphogenesis KW - localization Y1 - 2014 U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-115394 SN - 1932-6203 VL - 9 IS - 9 ER -