TY  - JOUR
A1  - Ludwig, K. U.
A1  - Sämann, P.
A1  - Alexander, M.
A1  - Becker, J.
A1  - Bruder, J.
A1  - Moll, K.
A1  - Spieler, D.
A1  - Czisch, M.
A1  - Warnke, A.
A1  - Docherty, S. J.
A1  - Davis, O. S. P.
A1  - Plomin, R.
A1  - Nöthen, M. M.
A1  - Landerl, K.
A1  - Müller-Myhsok, B.
A1  - Hoffmann, P.
A1  - Schumacher, J.
A1  - Schulte-Körne, G.
A1  - Czamara, D.
T1  - A common variant in Myosin-18B contributes to mathematical abilities in children with dyslexia and intraparietal sulcus variability in adults
JF  - Translational Psychiatry
N2  - The ability to perform mathematical tasks is required in everyday life. Although heritability estimates suggest a genetic contribution, no previous study has conclusively identified a genetic risk variant for mathematical performance. Research has shown that the prevalence of mathematical disabilities is increased in children with dyslexia. We therefore correlated genome-wide data of 200 German children with spelling disability, with available quantitative data on mathematic ability. Replication of the top findings in additional dyslexia samples revealed that rs133885 was a genome-wide significant marker for mathematical abilities\((P_{comb}=7.71 x 10^{-10}, n=699)\), with an effect size of 4.87%. This association was also found in a sample from the general population (P=0.048, n=1080), albeit with a lower effect size. The identified variant encodes an amino-acid substitution in MYO18B, a protein with as yet unknown functions in the brain. As areas of the parietal cortex, in particular the intraparietal sulcus (IPS), are involved in numerical processing in humans, we investigated whether rs133885 was associated with IPS morphology using structural magnetic resonance imaging data from 79 neuropsychiatrically healthy adults. Carriers of the MYO18B risk-genotype displayed a significantly lower depth of the right IPS. This validates the identified association between rs133885 and mathematical disability at the level of a specific intermediate phenotype.
KW  - disability
KW  - sulcal morphology
KW  - prelevance
KW  - identification
KW  - brain
KW  - cancer
KW  - association
KW  - developmental dyscalculia
KW  - tumor-suppressor gene
KW  - correlate
KW  - disorders
KW  - dyscalculia
KW  - dyslexia
KW  - genomic imaging
KW  - mathematics
KW  - quantitative trait
Y1  - 2013
U6  - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-131513
N1  - Supplementary Information accompanies the paper on the Translational Psychiatry website (http://www.nature.com/tp).
VL  - 3
IS  - e229
ER  - 
TY  - JOUR
A1  - Stepniak, Beata
A1  - Kästner, Anne
A1  - Poggi, Giulia
A1  - Mitjans, Marina
A1  - Begemann, Martin
A1  - Hartmann, Annette
A1  - Van der Auwera, Sandra
A1  - Sananbenesi, Farahnaz
A1  - Krüger-Burg, Dilja
A1  - Matuszko, Gabriela
A1  - Brosi, Cornelia
A1  - Homuth, Georg
A1  - Völzke, Henry
A1  - Benseler, Fritz
A1  - Bagni, Claudia
A1  - Fischer, Utz
A1  - Dityatev, Alexander
A1  - Grabe, Hans-Jörgen
A1  - Rujescu, Dan
A1  - Fischer, Andre
A1  - Ehrenreich, Hannelore
T1  - Accumulated common variants in the broader fragile X gene family modulate autistic phenotypes
JF  - EMBO Molecular Medicine
N2  - Fragile X syndrome (FXS) is mostly caused by a CGG triplet expansion in the fragile X mental retardation 1 gene (FMR1). Up to 60% of affected males fulfill criteria for autism spectrum disorder (ASD), making FXS the most frequent monogenetic cause of syndromic ASD. It is unknown, however, whether normal variants (independent of mutations) in the fragile X gene family (FMR1, FXR1, FXR2) and in FMR2 modulate autistic features. Here, we report an accumulation model of 8 SNPs in these genes, associated with autistic traits in a discovery sample of male patients with schizophrenia (N = 692) and three independent replicate samples: patients with schizophrenia (N = 626), patients with other psychiatric diagnoses (N = 111) and a general population sample (N = 2005). For first mechanistic insight, we contrasted microRNA expression in peripheral blood mononuclear cells of selected extreme group subjects with high-versus low-risk constellation regarding the accumulation model. Thereby, the brain-expressed miR-181 species emerged as potential "umbrella regulator", with several seed matches across the fragile X gene family and FMR2. To conclude, normal variation in these genes contributes to the continuum of autistic phenotypes.
KW  - permutation
KW  - miR-181
KW  - PGAS
KW  - FXR2
KW  - FXR1
KW  - FMR2
KW  - FMR1
KW  - identification
KW  - protein
KW  - fraxe mental retardation
KW  - CGG repeat
KW  - CPG Island
KW  - schizophrenia
KW  - expression
KW  - males
Y1  - 2015
U6  - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-136893
VL  - 7
IS  - 12
ER  - 
TY  - JOUR
A1  - Sharan, Malvika
A1  - Förstner, Konrad U.
A1  - Eulalio, Ana
A1  - Vogel, Jörg
T1  - APRICOT: an integrated computational pipeline for the sequence-based identification and characterization of RNA-binding proteins
JF  - Nucleic Acids Research
N2  - RNA-binding proteins (RBPs) have been established as core components of several post-transcriptional gene regulation mechanisms. Experimental techniques such as cross-linking and co-immunoprecipitation have enabled the identification of RBPs, RNA-binding domains (RBDs) and their regulatory roles in the eukaryotic species such as human and yeast in large-scale. In contrast, our knowledge of the number and potential diversity of RBPs in bacteria is poorer due to the technical challenges associated with the existing global screening approaches. We introduce APRICOT, a computational pipeline for the sequence-based identification and characterization of proteins using RBDs known from experimental studies. The pipeline identifies functional motifs in protein sequences using position-specific scoring matrices and Hidden Markov Models of the functional domains and statistically scores them based on a series of sequence-based features. Subsequently, APRICOT identifies putative RBPs and characterizes them by several biological properties. Here we demonstrate the application and adaptability of the pipeline on large-scale protein sets, including the bacterial proteome of Escherichia coli. APRICOT showed better performance on various datasets compared to other existing tools for the sequence-based prediction of RBPs by achieving an average sensitivity and specificity of 0.90 and 0.91 respectively. The command-line tool and its documentation are available at https://pypi.python.org/pypi/bio-apricot.
KW  - RNA-binding proteins
KW  - identification
KW  - characterization
Y1  - 2017
U6  - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-157963
VL  - 45
IS  - 11
ER  - 
TY  - JOUR
A1  - van Koolwijk, Leonieke M. E.
A1  - Ramdas, Wishal D.
A1  - Ikram, M. Kamran
A1  - Jansonius, Nomdo M.
A1  - Pasutto, Francesca
A1  - Hys, Pirro G.
A1  - Macgregor, Stuart
A1  - Janssen, Sarah F.
A1  - Hewitt, Alex W.
A1  - Viswanathan, Ananth C.
A1  - ten Brink, Jacoline B.
A1  - Hosseini, S. Mohsen
A1  - Amin, Najaf
A1  - Despriet, Dominiek D. G.
A1  - Willemse-Assink, Jacqueline J. M.
A1  - Kramer, Rogier
A1  - Rivadeneira, Fernando
A1  - Struchalin, Maksim
A1  - Aulchenko, Yurii S.
A1  - Weisschuh, Nicole
A1  - Zenkel, Matthias
A1  - Mardin, Christian Y.
A1  - Gramer, Eugen
A1  - Welge-Lüssen, Ulrich
A1  - Montgomery, Grant W.
A1  - Carbonaro, Francis
A1  - Young, Terri L.
A1  - Bellenguez, Céline
A1  - McGuffin, Peter
A1  - Foster, Paul J.
A1  - Topouzis, Fotis
A1  - Mitchell, Paul
A1  - Wang, Jie Jin
A1  - Wong, Tien Y.
A1  - Czudowska, Monika A.
A1  - Hofman, Albert
A1  - Uitterlinden, Andre G.
A1  - Wolfs, Roger C. W.
A1  - de Jong, Paulus T. V. M.
A1  - Oostra, Ben A.
A1  - Paterson, Andrew D.
A1  - Mackey, David A.
A1  - Bergen, Arthur A. B.
A1  - Reis, Andre
A1  - Hammond, Christopher J.
A1  - Vingerling, Johannes R.
A1  - Lemij, Hans G.
A1  - Klaver, Caroline C. W.
A1  - van Duijn, Cornelia M.
T1  - Common Genetic Determinants of Intraocular Pressure and Primary Open-Angle Glaucoma
JF  - PLoS Genetics
N2  - Intraocular pressure (IOP) is a highly heritable risk factor for primary open-angle glaucoma and is the only target for current glaucoma therapy. The genetic factors which determine IOP are largely unknown. We performed a genome-wide association study for IOP in 11,972 participants from 4 independent population-based studies in The Netherlands. We replicated our findings in 7,482 participants from 4 additional cohorts from the UK, Australia, Canada, and the Wellcome Trust Case-Control Consortium 2/Blue Mountains Eye Study. IOP was significantly associated with rs11656696, located in GAS7 at 17p13.1 (p = 1.4 x 10\(^{-8}\)), and with rs7555523, located in TMCO1 at 1q24.1 (p = 1.6 x 10\(^{-8}\)). In a meta-analysis of 4 case-control studies (total N = 1,432 glaucoma cases), both variants also showed evidence for association with glaucoma (p = 2.4 x 10\(^{-2}\) for rs11656696 and p = 9.1 x 10\(^{-4}\) for rs7555523). GAS7 and TMCO1 are highly expressed in the ciliary body and trabecular meshwork as well as in the lamina cribrosa, optic nerve, and retina. Both genes functionally interact with known glaucoma disease genes. These data suggest that we have identified two clinically relevant genes involved in IOP regulation.
KW  - expression
KW  - goldmann applanation tonometer
KW  - central corneal thickness
KW  - genome-wide scan
KW  - beaver-dam eye
KW  - to-disc ratio
KW  - onset
KW  - association
KW  - identification
KW  - population
Y1  - 2012
U6  - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-131378
VL  - 8
IS  - 5
ER  - 
TY  - THES
A1  - Goehtz, Florian
T1  - DNA-analytische Identifizierung unter Verwendung von frischem und gelagertem Skelettmaterial
T1  - Identification of fresh and ancient bone by DNA-analysis
N2  - Der DNA-analytischen Untersuchung von frischem und gelagertem Skelettmaterial kommt bei der Identifikation unbekannter Toter zunehmende Bedeutung zu, insbesondere in Fällen, in denen nur Skelettüberreste einer DNA-Analyse zur Verfügung stehen. Zur Aufklärung der praktischen Durchführbarkeit von Knochen-DNA-Typisierungen im rechtmedizinischen Laboralltag wurden 21 Knochenproben unterschiedlicher Liegezeit analysiert. 14 Knochenproben stammten aus Sektionsgut (Liegezeit von einer Stunde bis 41 Wochen), 7 Proben aus Skelett- bzw. Knochenfunden (geschätzte Liegezeit zwischen 10 und über 200 Jahren). Die DNA-Extraktion wurde mittels reversibler DNA-Bindung an einer Silica-Membran durchgeführt. Die Typisierung erfolgte im Rahmen eines Multiplex-PCR-Ansatzes unter Amplifizierung von neun STR-Loci und dem Amelogenin-Locus. Zusätzlich wurden drei besonders kurze, sog. vs-STRs bestimmt und exemplarisch für zwei Proben Bereiche des mt-Genoms sequenziert. Bei der Multiplex-Analyse ließ sich für 13 der 14 aus Sektionsgut gewonnenen Proben (93 %) ein komplettes, reproduzierbares Allelprofil gewinnen, an einer der Proben konnte nur eine molekulare Geschlechtszuordnung durchgeführt werden. Ebenso konnten alle drei vs-STR-Loci für 13 der 14 Proben reproduzierbar bestimmt werden; eine Probe war in einem der drei vs-STR-Loci typisierbar. Die sieben Proben aus Skelett- bzw. Knochenfunden waren bei der Multiplex-Analyse nicht reproduzierbar typisierbar, die Bestimmung der vs-STR-Loci führte im Fall der ältesten Probe zur Typisierung eines der drei Loci (TPOXvs). Bei zwei Proben, welche im Rahmen der nukleären DNA-Analyse kein reproduzierbares Ergebnis gebracht hatten, erfolgte die mt-DNA-Sequenzierung eines jeweils 234, bzw. 194 Nukleotide langen Segmentes der HV1-Region des mitochondrialen Genoms. Umwelteinflüsse und Lagerungsbedingungen haben mehr Einfluss auf den Erhaltungszustand der DNA in Knochenmaterial, als der Faktor Zeit. Die Analyse und Typisierung von Knochen-DNA hat sich als wichtiges Verfahren zur Identifizierung im rechtsmedizinischen Alltag etabliert, die unverändert unbefriedigenden Typisierungsergebnisse bei der Analyse älteren Knochenmaterials unterstreichen jedoch die Notwendigkeit der Weiterentwicklung zuverlässiger und effektiver Extraktions- und Aufreinigungsverfahren.
N2  - In recent years DNA-typing of fresh and ancient bone samples has become increasingly important for the identification of skeletal remains in the forensic context. To assess the efficiency and practicability of forensic DNA-typing 21 bone samples up to 200 years old were analysed. 14 samples were taken from forensic autopsies (post mortem interval 0 to 41 weeks), 7 samples came from accidental finds of skeletal remains (estimated post mortem intervall from 10 years to over 200 years). DNA-extraction was performed with a silica-based method, 9 STR and the Amelogenin-locus were amplified via PCR with a multiplex-kit, additionally 3 very-short-STRs were amplified and analysed. MtDNA-sequencing was carried out for two of the ancient bone samples. With the multiplex-kit 13 out of the 14 autopsy-derived samples (93 %) could be successfully analysed, for one sample only the Amelogenin-locus could be amplified. The 3 vs-STR-loci could be typed for 13 of the 14 samples, one sample only led to a successful analysis of one of the 3 vs-STRs. The 7 samples from accidental finds of skeletal remains yielded no result with the multiplex-kit, for one sample a vs-STR-locus could be analysed. Amplification and sequencing of a 234 and a 194 bp segement of the HV-1-region of the mtDNA could be obtained for two ancient bone samples where STR-loci could not be amplified. There are many factors leading to degradation of DNA in skeletal material, generally environmental conditions have more significance than time. Analysis and typing of bone-DNA has become an important procedure in the forensic routine, yet the results of this study show the need to further develop more efficient DNA-extraction and purification methods of bone samples.
KW  - Knochen
KW  - Identifizierung
KW  - DNA-Typisierung
KW  - STR
KW  - mtDNA
KW  - bone
KW  - identification
KW  - DNA-typing . STR
KW  - mtDNA
Y1  - 2006
U6  - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-18205
ER  - 
TY  - THES
A1  - Gebhard, Sebastian
T1  - DNA-analytische Untersuchungen an frischen und gelagerten Zähnen
T1  - DNA-analytical research with fresh and ancient teeth
N2  - In dieser Arbeit wurde überprüft, inwieweit sich verschiedene Lagerungsbedingungen von Zähnen auf die Verwertbarkeit von DNA im Zahninneren zur Gewinnung eines genetischen Fingerabdrucks auswirken. Die Untersuchungen an frisch extrahierten Zähnen ließen erkennen, dass die in dieser Arbeit verwendeten Methoden und DNA-Kits für die weitere Analyse der den unterschiedlichen Bedingungen ausgesetzten Zähne geeignet sind. Asensible Zähne weisen bereits bei der Zahnextraktion Zeichen von Degradation auf. Dagegen ist der kariöse Zerstörungsgrad an sich noch kein Ausschlusskriterium. Bei wurzelkanalbehandelten Zähnen konnten nur Systeme mit sehr kurzen Amplifikationsprodukten typisiert werden. Sie waren für eine genetische Identifizierung kaum geeignet. Bei der Analyse im Erdreich vergrabener Zähne nahm die Anzahl der typisierbaren Systeme nach einem Vierteljahr Liegezeit kontinuierlich ab, bis schließlich nach einem Jahr nur noch vereinzelt kleine Systeme detektiert werden konnten. Ein anderes Bild zeigte sich bei den in Wasser gelagerten Zähnen. Bis zu einem halben Jahr nach Versuchsbeginn konnte eine Typisierung aller Systeme durchgeführt werden. Erst nach einem Jahr war die Degradation so weit vorangeschritten, dass große Systeme keine Typisierung mehr erlaubten. Bei Zähnen, die der Sonnenstrahlung einen Monat ausgesetzt waren, war es dagegen problemlos möglich, einen vollständigen genetischen Fingerabdruck zu erfassen. Nach drei Monaten konnten allerdings nur noch vereinzelt sehr kleine Systeme gewonnen werden. Nach einem halben Jahr ergab lediglich der TPOX-vs eine erfolgreiche Typisierung. UV-Strahlung kann Zahnschmelz und –dentin durchdringen und DNA in recht kurzer Zeit degradieren. Die Zähne aus dem Sektionsgut des Instituts für Rechtsmedizin Würzburg lieferten unterschiedliche Ergebnisse, sodass hierzu keine generelle Aussage gemacht werden kann. Bei der Behandlung der Zähne mit Hitze von 200 °C konnte die DNA nur begrenzte Zeit vor Degradation geschützt werden. Bereits nach einer halben Stunde waren große Teile der Multiplex-Kits nicht mehr für eine Typisierung verwertbar. Das STR-System SE33 konnte allerdings noch ermittelt werden. Die Entnahmen zu späteren Zeitpunkten (60 min, 90 min und 120 min) lieferten fast nur noch einzelne STRSysteme. Eine knapp 30-jährige trockene Lagerung von Zähnen in einem Schrank mit Schutz vor Sonneneinstrahlung schadete der DNA-Analysierbarkeit kaum. Ein vollständiger Ausfall aller Systeme musste bei den Zahnproben von der Ausgrabung in Katzwang verzeichnet werden. Die Zähne dieser 380 bis 550 Jahre alten Schädel lieferten kein auswertbares DNA-Material mehr. Ebenso konnte mit diesen Untersuchungsmethoden aus den 2300 bis 2800 Jahre alten Zähnen aus der Dietersberghöhle kein analysierbares DNA-Material gewonnen werden. Es zeigte sich, dass Lagerbedingungen einen entscheidenden Einfluss auf die DNA-Qualität ausüben. Als DNA-schädigende Einflüsse können neben Mikroorganismen und Feuchtigkeit insbesondere UV-Strahlung und Hitze gelten. Der Faktor Zeit spielt bei günstigen Lagerbedingungen eine untergeordnete Rolle.
N2  - In this dissertation the possibility of winning a genetic fingerprint out of teeth that have been rested under different conditions was analysed. The examinations of recently extracted teeth showed that the methods and DNA-Kits used in this study are suitable for further analyses of teeth that have been exposed to different conditions. Asensible teeth already showed at time of extraction signs of degradation. However it was possible to get a genetic DNA-typing out of teeth which were destroyed by caries. Teeth with a root canal filling only showed systems with short amplification products. So they were not suitable for a genetic identification. The analysis of teeth which were buried in soil resulted that the number of detectable systems decreased continually after four month. After one year only a few systems were detected. The teeth which were stored in water gave a positive result in all systems after half a year. When the teeth have laid one year in water the degradation had gone so far that the big systems could not be typified anymore. Teeth that were exposed to sunshine for one month gave a complete detection of all analysed systems. Two month later only a few small systems were detected. After six months only the system TPOX-vs was successfully typed. UV-radiation gets through the dentin and the enamel and destroys the DNA very quickly. Two teeth out of the section good of the institute for forensic medicine showed completely different results. In one case the DNA-typing was successful, in the other one it wasn´t. Teeth that were treated in a 200 °C hot oven could protect the DNA for only a few minutes. After 30 minutes half of the analysed systems already were destroyed. After one hour and more only some sporadic systems were detected. The DNA-typing of a genetic fingerprint out of 30 years old teeth was successful. The complete failure of all systems showed examples of 380 to 550 years old teeth from a dig in Katzwang such as examples of 2.300 to 2.800 years old teeth out of the Dietersberg cave. For the DNA-quality it is very important to which conditions the teeth are exposed. DNA-damaging influences among other things are microorganisms, humidity, UV-radiation and heat. The factor time is not so important if the surrounding conditions are optimal.
KW  - DNA-typing
KW  - Genetischer Fingerabdruck
KW  - Zahn
KW  - Identifikation
KW  - alt
KW  - gelagert
KW  - DNA-typing
KW  - genetic fingerprint
KW  - teeth
KW  - ancient
KW  - identification
Y1  - 2009
U6  - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-46462
ER  - 
TY  - THES
A1  - Grimm, Dorothee
T1  - Entwicklung von neuen Nachweismethoden für Legionellen und Amöben und ihre Anwendung in ökologischen Studien
T1  - Development and evaluation of novel detection systems specific for legionellae and amoebae and their application in ecological studies
N2  - Legionella pneumophila wurde 1976 als Erreger der Legionellose, einer schweren Form von Lungenentzündung, identifiziert. Die inzwischen 42 Arten umfassende Gattung ist weltweit in aquatischen Biotopen verbreitet. Die Bakterien leben vergesellschaftet mit anderen Mikroorganismen in Biofilmen oder intrazellulär in Protozoen. Sie haben ein duales Wirtssystem, das heißt, sie sind in der Lage, sich sowohl in Einzellern als auch in humanen Phagozyten zu vermehren. Für die Erweiterung ihrer Habitate spielen verschiedene Umweltfaktoren eine Rolle. Eine exakte und schnelle Detektion und Identifikation der humanpathogenen Keime ist sowohl für die Lokalisierung der Infektionsquelle als auch für eine rechtzeitige Therapie der Patienten von großer Bedeutung. Die Technik der fluoreszierenden in situ Hybridisierung (FISH) basiert auf der Bindung einer spezifischen, mit einem Fluoreszenzfarbstoff markierten Oligonukleotidsonde an eine komplementäre Zielsequenz der ribosomalen RNA. In der vorliegenden Arbeit wurde für die in situ Hybridisierung eine neue 16S rRNA-gerichtete Sonde LEGPNE1 entwickelt, die spezifisch ist für L. pneumophila. In Versuchsreihen mit verschiedenen Bakterienkulturen wurden die Spezifität und Sensitivität der Gensonde ermittelt. LEGPNE1 erwies sich als artspezifisch und erkannte alle getesteten L. pneumophila-Stämme, ungeachtet ihrer Serogruppe. Nicht-pneumophila-Referenzstämme hybridisierten nicht mit der Sonde, ein einziger Basenaus-tausch in der Sequenz war für diese Unterscheidung ausreichend. Die Anwendung der Sonde wurde auch in Amöben-Infektionsassays und Umweltproben erfolgreich durchgeführt. Unterschiedliche, intrazellulär vorliegende Bakterien wurden von der Sonde spezifisch erkannt. Eine in situ Dokumentation der Infektions- und Vermehrungsrate war damit möglich. Durch die meist fakultativ intrazelluläre Lebensweise der Legionellen ist es wichtig, auch die Wirtszellen der Keime qualitativ zu detektieren und zu identifizieren. Die Entwicklung neuer Gensonden wurde daher auf die beiden bekannten Wirtsamöben Hartmannella und Naegleria ausgedehnt. Basierend auf Sequenzvergleichen wurden die gattungsspezifischen 18S rRNA-gerichteten Sonden HART498 und NAEG1088 konstruiert und in Versuchsreihen mit Referenzstämmen bei steigender Stringenz etabliert. Mit ihrer Hilfe konnten die Ergebnisse der zeit- und arbeitsaufwendigen Determination unbekannter Amöben anhand morphologischer Merkmale bestätigt werden. In situ Hybridisierungen mit einer Kombination von 16S und 18S rRNA-gerichteten Sonden wurden in Amöben-Infektionsassays mit Hartmannella vermiformis und L. pneumophila erfolgreich durchgeführt. Eine Interferenz der Sonden fand nicht statt. Die in situ Untersuchung der Struktur und Funktion komplexer mikrobieller Lebensgemeinschaften erfordert eine kultivierungsunabhängige und hochauflösende Methode, wie sie die fluoreszierende in situ Hybridisierung darstellt. Mit dem Ziel, mögliche Präferenzen der Legionellen für bestimmte Parameter, wie pH, Temperatur, elektrische Leitfähigkeit, Strömungsverhältnisse, zu erkennen und zu definieren, wurden mit Hilfe der neu entwickelten 16S rRNA-gerichteten Sonde 21 verschiedene Kaltwasserhabitate auf die Verbreitung von Legionella untersucht. Die Bakterien zeigten jedoch ein breites Toleranzspektrum gegenüber den gemessenen Parametern. Sie waren in nahezu allen beprobten Gewässern zu finden und ließen sich unabhängig von der Jahreszeit nachweisen. Die neue Sonde LEGPNE1 zeigte sich in in situ Hybridisierungen der Umweltproben als hochspezifisch. Mit ihr konnten auch nicht kultivierbare Legionellen detektiert werden. In drei Legionella-positiven Gewässern wurde außerdem das Vorkommen von Amöben untersucht. Es konnten insgesamt acht Amöbengattungen isoliert, kultiviert und bestimmt werden. Dominierend waren Stämme des nicht humanpathogenen Naegleria gruberi-Komplexes, Echinamoeba spp. und Echinamoeba-like Amöben. In einzelnen Proben wurden Acanthamoeba spp. Gruppe II, Hartmannella spp., Platyamoeba placida, Saccamoeba spp., Thecamoeba quadrilineata und Vexillifera spp. gefunden. Durch in situ Hybridisierung mit den neuen 18S rRNA-gerichteten Sonden HART498 und NAEG1088 konnten die Ergebnisse der morphologischen Bestimmung der Amöben bestätigt werden. Auch die Amöben zeigten keine Präferenzen bezüglich der in den Standorten gemessenen Wasserparameter. Die in situ Hybridisierung mit rRNA-gerichteten Gensonden erlaubt eine Analyse der Struktur und Dynamik von Biozönosen, ermöglicht aber keine Aussage über die speziellen Aktivitäten der nachgewiesenen Bakterien. Eine Lösung hierfür könnte der spezifische in situ Nachweis von mRNA-Molekülen darstellen. Ein Problem hierbei stellt ihre, im Vergleich zu anderen Molekülen wie rRNA, sehr kurze Halbwertszeit und das Vorhandensein von nur wenigen Kopien pro Zelle dar. Daher ist im Anschluss an die in situ Hybridisierung in den meisten Fällen eine Signalamplifikation nötig, um ein detektierbares Signal zu erhalten. In dieser Arbeit sollte die für das iap-Gen in Listeria monocytogenes entwickelte Methode zum Nachweis der mip-mRNA in L. pneumophila etabliert werden. Erste Anwendungen in Dot blot- und in situ Hybridisierungen mit mehrfach DIG-markierten Polyribonukleotidsonden bzw. mit simultan eingesetzten, einfach DIG-markierten Oligonukleotiden zeigten noch nicht die gewünschte Spezifität. Diese Ergebnisse stellen jedoch eine wichtige Grundlage für zukünftige Experimente dar.
N2  - Legionella pneumophila was identified in 1976 as the causative agent of a life-threatening atypical pneumonia. Today the genus comprises about 42 species which are spread worldwide in aquatic biotopes. The bacteria live in association with other microorganisms in biofilms as well as intracellularly in protozoa. They have a dual host system which means that they are able to replicate both in protozoans and in human phagocytes. Several environmental factors are known to play a role in their distribution. The ability to quickly detect and to exactly identify these potential human pathogens is important in order to recognize reservoirs for disease as well as to treat patients in due time. Fluorescence in situ hybridization (FISH) is a technique based on the reaction of a specific oligonucleotide, labeled with a fluorescence marker, with the complementary rRNA target region. In this work a new 16S rRNA-targeted oligonucleotide probe LEGPNE1 for in situ hybridization was developed, which is specific for L. pneumophila. The specificity and the sensitivity of the probe were evaluated in experiments with different bacterial cultures. LEGPNE1 was demonstrated to be highly species-specific recognizing all tested strains of L. pneumophila independently of the serogroup. Non-pneumophila reference strains did not hybridize with the probe. Only one mismatch in the sequence was shown to be sufficient for the oligonucleotide to distinguish between complementary and nearly complementary sequences. The probe was also applied successfully to infected amoebal cells and environmental samples. Different bacteria located intracellularly were recognized specifically by the probe. This allows the in situ monitoring of bacterial infection and multiplication rates in amoebae. As legionellae presumably live most of the time as intracellular parasites, it is also important to be able to detect their hosts. Therefore, the design of new probes was extended to cover two known host amoebal genera, Hartmannella and Naegleria. Based on comparative sequence analysis the genus-specific 18S rRNA-targeted probes HART498 and NAEG1088 were constructed. Subsequently they were tested in hybridization series with different reference strains and gradually increasing stringency. Amoebal strains which had been identified previously based on their morphological features could be reconfirmed using in situ hybridization with these new oligonucleotides. In situ hybridization experiments of infection assays with Hartmannella vermiformis and Legionella pneumophila using a combination of 16S and 18S rRNA-targeted probes were done successfully. Interference of the probes with the results of the tests was not observed. For the analysis of the composition of complex microbial communities a culture-independent and highly specific method is required. This can be achieved by the fluorescence in situ hybridization. In order to determine potential preferences of legionellae for water parameters such as pH, temperature, conductivity, or water current, twenty-one different cold water habitats were examined for the presence of Legionella using the newly designed 16S rRNA-targeted oligonucleotide probe. The bacteria were shown to be able to tolerate a broad range of the measured parameters. They could be found in nearly all of the habitats investigated independent of the season. The new probe LEGPNE1 was proved to detect L. pneumophila in environmental samples highly specifically, even if the cells were in a nonculturable state. Three Legionella-positive sampling sites were examined for the presence of amoebae. Using traditional culture methods followed by morphological determination, eight amoebal genera could be isolated and identified. Most abundant were strains of the apathogenic Naegleria gruberi-complex, Echinamoeba spp. and Echinamoeba-like amoebae. Other species including Acanthamoeba spp. (sequence type II), Hartmannella spp., Platyamoeba placida, Saccamoeba spp., Thecamoeba quadrilineata and Vexillifera spp. were found sporadically. In situ hybridization experiments using the new 18S rRNA-targeted oligonucleotide probes HART498 and NAEG1088 confirmed the determinations done by morphological criteria. Concomitant analysis of selected water parameters revealed no preference of the protozoa for certain environmental conditions. In situ hybridization with rRNA-targeted oligonucleotide probes is a powerful tool to analyze structure and dynamics in biocenosis. However, this technique does not provide much information about the in situ function of the detected bacteria. The specific in situ detection of mRNA molecules allows to narrow this gap. One problem in the application of this method is the instability and low copy number of mRNA in each cell compared to other molecules like rRNA. Therefore, a signal amplification posterior to the in situ hybridization is required in most cases in order to generate a detectable signal. In this work the detection of the mRNA of mip in L. pneumophila was to be established using a protocol developed for the detection of iap in Listeria monocytogenes. However, first applications of dot blot and in situ hybridizations using DIG-conjugated polyribonucleotide probes and several DIG-labeled oligonucleotides applied simultaneously did not show the neccessary specificity. This technical approach will be essential for further experiments in this field of research.
KW  - Legionella pneumophila
KW  - Freilebende Amöben
KW  - Nachweis
KW  - Ökosystem
KW  - Legionella pneumophila
KW  - freilebende Süßwasseramöben
KW  - Nachweis
KW  - Bestimmung
KW  - 16S rRNA
KW  - 18SrRNA
KW  - fluoreszierende in situ Hybridisierung
KW  - Legionella pneumophila
KW  - free-living freshwater amoebae
KW  - detection
KW  - identification
KW  - 16S rRNA
KW  - 18SrRNA
KW  - fluorescence in situ hybridization
Y1  - 2000
U6  - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-1351
ER  - 
TY  - JOUR
A1  - Hoffmann, Linda S
A1  - Schmidt, Peter M
A1  - Keim, Yvonne
A1  - Hoffmann, Carsten
A1  - Schmidt, Harald H H W
A1  - Stasch, Johannes-Peter
T1  - Fluorescence Dequenching Makes Haem-Free Soluble Guanylate Cyclase Detectable in Living Cells
JF  - PLOS ONE
N2  - In cardiovascular disease, the protective NO/sGC/cGMP signalling-pathway is impaired due to a decreased pool of NO-sensitive haem-containing sGC accompanied by a reciprocal increase in NO-insensitive haem-free sGC. However, no direct method to detect cellular haem-free sGC other than its activation by the new therapeutic class of haem mimetics, such as BAY 58-2667, is available. Here we show that fluorescence dequenching, based on the interaction of the optical active prosthetic haem group and the attached biarsenical fluorophor FlAsH can be used to detect changes in cellular sGC haem status. The partly overlap of the emission spectrum of haem and FlAsH allows energy transfer from the fluorophore to the haem which reduces the intensity of FlAsH fluorescence. Loss of the prosthetic group, e. g. by oxidative stress or by replacement with the haem mimetic BAY 58-2667, prevented the energy transfer resulting in increased fluorescence. Haem loss was corroborated by an observed decrease in NO-induced sGC activity, reduced sGC protein levels, and an increased effect of BAY 58-2667. The use of a haem-free sGC mutant and a biarsenical dye that was not quenched by haem as controls further validated that the increase in fluorescence was due to the loss of the prosthetic haem group. The present approach is based on the cellular expression of an engineered sGC variant limiting is applicability to recombinant expression systems. Nevertheless, it allows to monitor sGC's redox regulation in living cells and future enhancements might be able to extend this approach to in vivo conditions.
KW  - spontaneously hypersensitive-rats
KW  - nitric-oxide
KW  - down-regulation
KW  - energy-transfer
KW  - cyclic-gmp
KW  - protein
KW  - activation
KW  - identification
KW  - in-vivo
KW  - no
Y1  - 2011
U6  - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-139631
VL  - 6
IS  - 8
ER  - 
TY  - JOUR
A1  - Gupta, Shishir K.
A1  - Srivastava, Mugdha
A1  - Osmanoglu, Oezge
A1  - Dandekar, Thomas
T1  - Genome-wide inference of the Camponotus floridanus protein-protein interaction network using homologous mapping and interacting domain profile pairs
JF  - Scientific Reports
N2  - Apart from some model organisms, the interactome of most organisms is largely unidentified. High-throughput experimental techniques to determine protein-protein interactions (PPIs) are resource intensive and highly susceptible to noise. Computational methods of PPI determination can accelerate biological discovery by identifying the most promising interacting pairs of proteins and by assessing the reliability of identified PPIs. Here we present a first in-depth study describing a global view of the ant Camponotus floridanus interactome. Although several ant genomes have been sequenced in the last eight years, studies exploring and investigating PPIs in ants are lacking. Our study attempts to fill this gap and the presented interactome will also serve as a template for determining PPIs in other ants in future. Our C. floridanus interactome covers 51,866 non-redundant PPIs among 6,274 proteins, including 20,544 interactions supported by domain-domain interactions (DDIs), 13,640 interactions supported by DDIs and subcellular localization, and 10,834 high confidence interactions mediated by 3,289 proteins. These interactions involve and cover 30.6% of the entire C. floridanus proteome.
KW  - interaction map
KW  - drosophila
KW  - identification
KW  - evolutionary
KW  - reliability
KW  - annotation
KW  - database
KW  - target
KW  - cycle
Y1  - 2020
U6  - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-229406
VL  - 10
IS  - 1
ER  - 
TY  - JOUR
A1  - Sass, Andrea M.
A1  - Van Acker, Heleen
A1  - Förstner, Konrad U.
A1  - Van Nieuwerburgh, Filip
A1  - Deforce, Dieter
A1  - Vogel, Jörg
A1  - Coenye, Tom
T1  - Genome-wide transcription start site profiling in biofilm-grown Burkholderia cenocepacia J2315
JF  - BMC Genomics
N2  - Background: Burkholderia cenocepacia is a soil-dwelling Gram-negative Betaproteobacterium with an important role as opportunistic pathogen in humans. Infections with B. cenocepacia are very difficult to treat due to their high intrinsic resistance to most antibiotics. Biofilm formation further adds to their antibiotic resistance. B. cenocepacia harbours a large, multi-replicon genome with a high GC-content, the reference genome of strain J2315 includes 7374 annotated genes. This study aims to annotate transcription start sites and identify novel transcripts on a whole genome scale. Methods: RNA extracted from B. cenocepacia J2315 biofilms was analysed by differential RNA-sequencing and the resulting dataset compared to data derived from conventional, global RNA-sequencing. Transcription start sites were annotated and further analysed according to their position relative to annotated genes. Results: Four thousand ten transcription start sites were mapped over the whole B. cenocepacia genome and the primary transcription start site of 2089 genes expressed in B. cenocepacia biofilms were defined. For 64 genes a start codon alternative to the annotated one was proposed. Substantial antisense transcription for 105 genes and two novel protein coding sequences were identified. The distribution of internal transcription start sites can be used to identify genomic islands in B. cenocepacia. A potassium pump strongly induced only under biofilm conditions was found and 15 non-coding small RNAs highly expressed in biofilms were discovered. Conclusions: Mapping transcription start sites across the B. cenocepacia genome added relevant information to the J2315 annotation. Genes and novel regulatory RNAs putatively involved in B. cenocepacia biofilm formation were identified. These findings will help in understanding regulation of B. cenocepacia biofilm formation.
KW  - persistence
KW  - genomic islands
KW  - pathogen
KW  - identification
KW  - bacteria
KW  - small RNAs
KW  - translation initiation
KW  - cepedia complex
KW  - global gene expression
KW  - SEQ
KW  - resistance
KW  - burkholderia cenocepacia
KW  - biofilms
KW  - dRNA-Seq
KW  - transcription start site
KW  - antisense RNA
Y1  - 2015
U6  - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-139748
VL  - 16
IS  - 775
ER  -