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The present paper is a continuation of "The Birds of the Galapagos Islands, with Observations all the Birds of Clipperton and Cocos Islands (Columbiformes to Pelecaniformes)". The collection of land bird skins brought back by the Expedition numbers 5,916, exclusive of the Galapagos Dove. The writer lacks the time to study this large number of specimens and therefore deems it advisable to publish his field notes without further delay. In addition to the skins, considerable collections of eggs, nests, and birds and stomachs in alcohol were macle. These also await investigation. The land birds of Cocos Island, Costa Rica, and of the Galapagos Islands are treated in the present connection, with the exception of the Galapagos Dove already considered in the earlier paper. The sequence and nomenclature of species in both papers is that of Sharpe's "Hand-list of the Genera and Species of Birds." As the species of the genera Geospiza and Camarhynchus demand a thorough revision with all available material at hand, the writer uses provisionally, with a few changes, the specific names as defined by Messrs. Rothschild and Hartert and Messrs. Snodgrass and Heller. Wherever the writer fails to recognize a species admitted by these authors, the rejected name is placed in a. selected synonymy. The localities listed for each species also include those mentioned by Messrs. Salvin, Ridgway, Rothschild and Hartert, and Snodgrass and Heller. For a full, description of the botanical regions or zones (dry or arid, moist or humid, and grassy, in order from seashore to mountain top) mentioned in this paper, the reader should refer to Mr. Alban Stewart's paper "A Botanical Survey of the Galapagos Islands."
This paper is a general review of the problem of clutch-size in birds. It grew out of a search through the literature to see to what extent clutch-size trends found in the Robin, Erithaau8 rebecula, might apply generally. Part I. describes those types of clutch-size variation found within any species, Part II. provides a general discussion of the factors involved. In Part IlI, which follows separately later, some of the differences between different species of birds will be considered. Examples are taken mainly from European birds, hence this review is in some ways supplementary to that on African birds by Moreau (1944), to which the present study owes a considerable debt.
The respiratory chain is composed of protein complexes residing in the inner mitochondrial membrane of eukaryotes or in the cytoplasmic membrane of prokaryotes. This cellular energy converter transforms a redox potential stored in low potential substrates into an electrochemical potential across the respective membrane. Typical respiratory chains contain the complexes I, II, III and IV named according to their sequence in the respiratory chain reaction. Electrons of low potential substrates enter at complex I or II and are passed via complex III to complex IV where they are transferred to oxygen. The transport of electrons between the complexes is mediated by small electron shuttles like quinol or cytochrome c. Two different models describe their exchange either by (1) random collision of freely diffusible electron shuttles and membrane protein complexes or (2) arrangement of the complexes in supercomplexes enabling direct channeling of electron shuttles. In the Gram positive bacterium Corynebacterium glutamicum, the complex III to complex IV electron shuttle cytochrome c is not diffusible but a covalently bound part of the diheme cytochrome subunit QcrC of complex III. Therefore, the complexes III and IV have to form a supercomplex for electron transduction. The aim of this thesis was to purify and characterise this obligatory supercomplex III/IV of C. glutamicum. To gain sufficient biomass of C. glutamicum as starting material for purification, a phosphate buffered minimal medium was developed that enabled yield of total 120 g wet cell mass (38 g dry mass) in 12 L (6×2 L) shaking cultures. The determined conversion factor of glucose into biomass was 0.46 g/g indicating an intact respiratory chain. The yield was increased by bioreactor cultivation to ~690 g wet cell mass (~220 g dry mass) in ~10 L culture volume. A previously described homologous expression system was applied that produces the complex IV subunit CtaD with a fused Strep-tag II to facilitate purification. Affinity purifications using the Strep-tag II affinity to Strep-Tactin resin yielded a mixture of complexes and supercomplexes. Two supercomplex III/IV versions named supercomplex A and B and free complex IV were identified in this mixture by size exclusion chromatography, redox difference spectroscopy and two dimensional polyacrylamide gel electrophoresis including blue native polyacrylamide electrophoresis. The here presented downscaled blue native polyacrylamide electrophoresis method with analysis times of ~1 h enabled efficient screening of factors influencing the stability of supercomplex III/IV. The screening resulted that the integrity of supercomplex III/IV is preserved by using neutral detergents at minimal detergent to protein ratios for solubilisation and low detergent concentrations for purification and storage slightly above the required critical micellar concentration. Furthermore, pH <=7.5 is required for stability of supercomplex III/IV. Large biomass yields enabled upscaling of supercomplex III/IV affinity purification. Application of the identified stability conditions resulted in affinity purified samples free of supercomplex B. The major component supercomplex A was efficiently separated from residual free complex IV by preparative size exclusion chromatography. Concentration of purified supercomplex A by ultracentrifugation resulted in integrity of the supercomplex for several days at 4 °C. Purified supercomplex A contains ten different previously described subunits. The heme content of supercomplex A relative to the protein mass is heme A: 6.0 μmol/g, heme B: 6.5 μmol/g, and heme C: 5.8 μmol/g determined by redox difference spectroscopy and biochemical protein quantification. This indicates an equimolar ratio of complex III and complex IV in supercomplex A. Supercomplex A has quinol oxidase activity that is inhibited by stigmatellin or sodium azide. The turnover number of transferred electrons per complex III monomer is 148 s−1 at 25° C. The homogeneity and stability of the prepared supercomplex A enabled the growth of threedimensional crystals of up to 0.1 mm in length. Their composition of supercomplex A was verified by redox difference spectroscopy of intact crystals and blue native polyacrylamide electrophoresis of dissolved crystals. The crystals diffracted X-rays corresponding to a resolution of ~10 Å. Electron microscopy of negative stained samples revealed the uniform shape of purified supercomplex A particles with dimensions of 22 × 9 nm in the view plane. Combined heme quantification, size determination, determined activity, symmetry considerations, and particle shape indicate that supercomplex A has a central dimer of complex III and two monomers of complex IV on opposite sides. This conformation is functionally reasonable because it provides each complex III monomer with one complex IV monomer as electron acceptor. Therefore, the stoichiometry of supercomplex A is most likely III2IV2. The sensitivity of supercomplex A to detergents indicated a role of phospholipids in its stability. Therefore, a method for phospholipid identification and quantification was developed that is suitable for detergent solubilised crude and purified membrane protein samples. The analysis combines separation of phospholipid classes according to their head group by normal phase high performance liquid chromatography with evaporative light scattering detection. Calibration with external standard allows quantification of phospholipid amount in the range of 0.25-12 μg. The method is verified by analysing the phospholipid content of the well characterised complex III of Saccharomyces cerevisiae. The reduction of its phospholipid content during its purification steps is monitored. The complex III sample purified to crystallisation quality contains the phospholipid content that was also observed in previously reported structures determined by X-ray crystallography. Purified stable supercomplex A from C. glutamicum revealed a large content of bound phospholipids. The main differences between intact supercomplex A and a mixture of potentially disintegrated smaller complexes is that intact supercomplex A has a doubled phosphatidic acid content and an increased phosphatidyl glycerol content. The importance of the small anionic phosphatidic acid for mediation of contacts between complexes in a supercomplex is discussed. The total phospholipid content of stable supercomplex A is sufficient for a complete belt surrounding the supercomplex in the membrane plane. This indicates that also all essential internal phospholipid binding positions are occupied and potentially stabilise supercomplex A.
On Urnatella gracilis
(1893)
Evidence from archaeological fish bone assemblages from the southern North Sea region of Europe is used to illuminate fishing, fish consumption and fish trade from the 1st to the 16th century AD. The fish species represented in the material indicate a very strong influence from the local fish fauna at almost all sites. The species and size of the fish indicate that several fishing methods have been employed throughout the period studied, including nets, hooks and weirs. A chronological development in fishing, for example, a tendency towards more sea-going fishing, is reflected in the fish bone assemblages in some countlres. Evidence from fishing in the Baltic region from the 5th century BC to the 16th century AD is included in the discussion. Indications of fish trade include bones of exotic species (for instance, matinc species at inland sites) and an unbalanced representation of skeletal clements (trade with decapitated stockfish or gillless hering). Of particular interest are assemblages which indicate a fish industry, for instance, large-scale processing (removal of gills) of herring in 13th century Denmark.
Observations on fish scales
(1913)
Ataxin-2 is a novel protein, within which the unstable expansion of a polyglutamine domain can cause Spinocerebellar Ataxia type 2 (SCA2), a neurodegenerative disease which belongs to the group of polyglutamine disorders. SCA2 is characterised by a progressive loss of neurons that first affects the cerebellum and brain stem and then may extend to other areas of the brain, like substantia nigra, motoneurons and thalamus. Several lines of research have attempted to determine therole of ataxin-2 in its normal and mutant version. Different animal models and cell culture approaches to study ataxin-2 function implicated ataxin-2 in RNA processing, embryonic development, apoptosis and cytoskeleton. However, the function of ataxin-2 still remains unclear. In this thesis, a protein interaction approach was chosen as an alternative to gain insights into the cellular function of ataxin-2. Full-length ataxin-2 was used as bait in a yeast two-hybrid screen of human adult brain cDNA. Among five candidate interactor proteins identified, two were the endophilins A1 and A3, proteins involved in vesicle endocytosis. Co-immunoprecipitation studies confirmed the association of these proteins in an endogenous complex of mouse brain. In vitro binding experiments narrowed the binding interfaces down to two proline-rich domains on ataxin-2, which interacted with the SH3 domain of endophilins A1/A3. Ataxin-2 and endophilins A1/A3 colocalised at the endoplasmic reticulum as determined by immunofluorescence microscopy of transfected cell lines, and by centrifugation fractionation studies of mouse brain. Importantly, the pattern observed in transfected cells was conserved in untransfected rat hippocampal neurons. In mouse brain, associations of ataxin-2 with endocytic proteins such as the adaptor CIN85, the ubiquitin ligase c-Cbl and also GRB2, in the last case by means of a SH3 domain array chip, were also demonstrated. GST pull-down assays showed ataxin-2 to interact directly with the SH3 domains A and C of CIN85, the C-terminal SH3 domain of GRB2, and the SH3 domain of Src, a kinase activated after receptor stimulation. Functional studies demonstrated that ataxin-2 affects endocytic trafficking of the epidermal growth factor receptor (EGFR) by reducing the EGFR internalisation after EGF stimulation. Taken together, these data implicate ataxin-2 to play a role in endocytic receptor cycling.
Genetic analysis of salt adaptation in Methanosarcina mazei Gö1 : the role of abl, ota and otb genes
(2008)
1. M. mazei ist ein halotolerantes methanogenes Archäon und akkumuliert kompatible Solute als längerfristige Anpassung an erhöhte Osmolarität in der Umgebung. Bei intermediären Salzkonzentrationen (~ 400 mM NaCl) wird vorzugsweise α-Glutamat gebildet und bei höheren Salzkonzentrationen (~ 800 mM NaCl) wird Nε-Acetyl-ß-Lysin zusätzlich zu Alpha-Glutamat synthetisiert. 2. Eine Analyse der intrazellulären Solutezusammensetzung mittels NMR ergab, dass M. mazei Glycin-Betain als Osmolyt akkumulieren kann. Für die Aufnahme von Glycin-Betain konnten zwei putative Glycin-Betain-Transporter in M. mazei identifiziert werden, Ota und Otb. Ota steht für „osmoprotectant transporter A“ und Otb für „osmoprotectant transporter B“. Das Genom von M. mazei wurde, nachdem es vollstänidg sequenziert war, nach Genen durchsucht, die eine Rolle bei der Aufnhame von Glycin-Betain oder anderen kompabtiblen Solute spielen könnten. Dafür wurde die Sequenz eines Substratbindeproteins eines bekannten bakteriellen Glycin-Betain-Transporters, opuAC aus B. subtillis als Referenzsequenz verwendet. Hierbei konnte ein Homolog, otaC, in M. mazei identifiziert werden. otaC ist Teil eines Genclusters, welches für einen ABC-Transporter kodiert. otb wurde bei einer genomweiten Expressionsanalyse zur Salzadaptation von M. mazei identifiziert. Es wurden Gene eines putativen ABC-Transporters identifiziert, die unter Hochsalzbedingungen leicht induziert waren. Es stellte sich heraus, dass es sich hierbei um einen zweiten putativen Glycin-Betain-Transporter handelte. Otb gehört auch zur Familie der ABC-Transporter. Vergleichsanalysen zeigten, dass die beiden Transporter keine große Ähnlichkeit zueinander aufweisen. Die Funktion und Rolle der beiden ABC-Transporter, vor allem von Otb, war zu Beginn dieser Arbeit unklar. 3. Bei Analysen des intrazellulären Solutepools im Wildtyp von M. mazei stellte sich heraus, dass in Anwesenheit von Glycin-Betain die Konzentration von Glutamat und NE- Acetyl-ß-Lysin verringert war. Bei 400 mM NaCl reduzierte Glycin-Betain die Glutamat- Konzentration um 16% und bei 800 mM NaCl um 29%. Besonders deutlich zeigte sich der Einfluß von Glycin-Betain bei der Akkumulation von NE-Acetyl-ß-Lysin. Bei 400 mM NaCl reduzierte Glycin-Betain die Konzentration an NE-Acetyl-ß-Lysin um 60% und bei 800 mM NaCl um 50%. Der Einfluß von Glycin-Betain konnte auf verschiedenen Ebenen in M. mazei beobachten werden. Es konnte gezeigt werden, dass die relative Transkriptimenge von ota unter Hochsalzbedingungen zunimmt. Glycin-Betain reduzierte die Transkription von ota bei verschiedenen Salzkonzentrationen. Die relative Transkriptmenge an mRNA von ota wurde mittels quantitativer real-time PCR (qRT-PCR) quantifiziert und war bis zu 52% reduziert in Zellen, die in Gegenwart von Glycin-Betain gewachsen waren. Die Transkriptmenge von otb war unter den gleichen Bedingungen nicht beeinflusst und zeigte generell keine Zunahme mit der Salinität des Mediums. Des Weiteren konnte ein Effekt von Glycin-Betain auf Ebene der Transportaktivität von Ota gezeigt werden. Hier zeigte sich, dass Zellen, die bei 400 mM NaCl in Gegenwart von Glycin-Betain gezogen waren, eine geringere Transportaktivität aufweisen, als Zellen, die bei 400 mM NaCl ohne Glycin-Betain gewachsen waren. Die Transportaktivität war um 90% geringer. Es muss jedoch berücksichtigt werden, dass es sich bei den Zellen, die ohne Glycin-Betain gewachsen waren, um eine Nettoaufnahme von Glycin-Betain handelte. Im Gegensatz dazu, ist davon auszugehen, dass Zellen, die in Gegenwart von Glycin-Betain gewachsen waren, eine Austaschreaktion zwischen bereits vorhandenem intrazellulärem und extrazellulär angebotenem Glycin-Betain vornehmen. [Die dem letzten Punkt zugrundeliegenden Daten wurden von Silke Schmidt im Rahmen einer Diplomarbeit erhoben, die von mir mitbetreut wurde. Aus Gründen der vollständigen Darstellung des Projektverlaufes werden diese Daten mitaufgeführt.] 4. Zur weiteren Klärung der Rolle und Funktion der beiden putativen Glycin-Betain- Transporter Ota und Otb war es Ziel, Mutantenstudien durchzuführen. Eine Vorraussetzung für die Generierung von Mutanten ist, dass der Organismus auf Agarplatten wächst und Einzelkolonien von einer einzelnen Zelle ausgehend bildet. Dies ist ein wichtiger Punkt bei Methanosarcina spp., die Zellpakete, sogenannte Sarcinen bilden. Deshalb wurde zunächst nach den optimalsten Plattierungsbedingungen gesucht, unter denen M. mazei keine Sarcinen bildet und die Plattierungseffizienz am höchsten war. Die Plattierungseffizienz betrug im Durchschnitt 54%. Für das Einbringen von DNA in die Zellen wurde eine Liposomen-vermittelte Transformation getestet. Ein ähnliches Vorgehen war bereits für Methanosarcina acetivorans beschrieben, konnte bislang aber noch nicht erfolgreich für M. mazei Gö1 und andere Stämme von M. mazei angwendet werden. Erste Schritte zur Anpassung des Transformations-Protokolles beinhalteten das Testen von DOTAP verschiedener Hersteller, sowie die Konzentration an eingesetzter DNA. Das jeweilige Zielgen/Zieloperon, welches deletiert werden sollte, wurde durch eine pac-Kassette ersetzt. Diese kodiert für eine Puromycin-Transacetylase und verleiht dem Organismus Puromycin- Resistenz. Die pac-Kassette wurde von umgebenden Bereichen des Ziellocus flankiert und integrierte mit Hilfe dieser flankierenden Bereiche über doppelt-homologe Rekombination in das Genom. 5. Mit dem oben beschriebenen Verfahren wurden ota::pac- und otb::pac-Mutanten erzeugt und über Southern-Blot Analyse verifiziert. Eine erste Charakterisierung der Mutanten mittels qRT-PCR zeigte, dass auf mRNA-Ebene keine Transkripte von ota in M. mazei ota::pac oder otb in M. mazei otb::pac nachweisbar waren. Zusätzlich konnte auf Proteinebene das Substratbindeprotein OtaC in M. mazei ota::pac und OtbC in M. mazei otb::pac nicht über einen Antikörper gegen das jeweilige Substratbindeprotein nachgewiesen, was die erfolgreiche Deletion bestätigte. Erste phänotypische Charakterisierungen zeigten, dass das Wachstum von M. mazei ota::pac und M. mazei otb::pac unter Hochsalzbedingungen nicht beeinträchtigt und vergleichbar mit dem des Wildtyps war. Auch bei kälteren Wachstumstemperaturen von 22°C wuchsen die Mutanten ohne Phänotyp. 6. Radioaktive Transportstudien mit M. mazei otb::pac zeigten, dass diese Mutante, die noch ein funktionelles Ota besitzt, [14C]Glycin-Betain aufnehmen kann. Es stellte sich heraus, dass diese Mutante eine höhere Transportrate für Glycin-Betain aufwies, als der Wildtyp. Die Aufnahmerate war um einen Faktor 2 höher als beim Wildtyp. Zusätzlich konnten qRT-PCR Analysen zeigen, dass die relative Transkriptmenge an ota in der otb::pac-Mutante um einen Faktor 2 höher war, als im Wildtyp. Umgekehrt konnte dieser Effekt nicht beobachtet werden, d.h. eine erhöhte Transkriptmenge an otb in M. mazei ota::pac. Auf Proteinebene konnte beobachtet werden, dass die intrazelluläre Konzentration an OtaC in der Mutatne leicht höher war als im Wildtyp. Jedoch stellte sich heraus, dass die intrazelluläre Glycin-Betain-Konzentration bei 400 mM NaCl in der Mutante nicht erhöht war verglichen mit Wildtyp, sondern die Konzentrationen gleich waren. Bei höheren Salzkonzentrationen (800 mM NaCl) zeigte sich jedoch ein anderes Bild: die intrazelluläre Glycin-Betain-Konzentration war in der Mutante um 60% erhöht. Dies könnte auf die erhöhte Transportaktivität von M. mazei otb::pac zurückzuführen sein. Die Konzentration anderer kompatibler Solute wie Glutamat und NE-Acetyl-ß-Lysin waren in diesen Zellen bis zu 48% reduziert. In vorherigen Studien konnte gezeigt werden, dass heterolog überproduziertes Ota von M. mazei in E. coli MKH13, eine E. coli-Mutante, die keine Glycin-Betain-Transporter mehr besitzt, die Aufnahme von Glycin-Betain wieder herstellen konnte [die Daten von ota in E. coli MKH13 wurden in der bereits oben erwähnten Diplomarbeit von Silke Schmidt erhoben]. Zur Klärung der Funktion von Otb wurde der gleiche Versuch mit otb in E. coli MKH13 durchgeführt. Jedoch konnte eine heterologe Produktion von Otb aus M. mazei die Aufnahme von Glycin-Betain in E. coli MKH13 nicht wieder herstellen. Hierbei wurde über Western-Blot Analyse sichergestellt, dass Otb tatsächlich in der Membran vorhanden war. Auch Transportstudien mit der Mutante M. mazei ota::pac zeigten, dass diese Mutante kein [14C]Glycin-Betain mehr aufnehmen konnte. Es konnte auch keine Akkumulation von Glycin-Betain mittels NMR in dieser Mutante gemessen werden. Des Weiteren zeigte sich, dass die intrazellulären Konzentrationen an Glutamat und Nε-Acetyl-ß-Lysin bei 400 mM und 800 mM NaCl in der Mutante unbeeinflusst von der Glycin-Betain-Konzentration im Medium waren. Weitere Transportstudien mit M. mazei ota::pac zur Aufnahme von [14C]Cholin zeigten, dass dieses Molekül weder vom Wildtyp, noch von der Mutante aufgenommen wurde. Dieses Ergebnis wurde durch Messung des Solutepools mittels NMR bestätigt. Somit kann ausgeschlossen werden, dass Otb unter den gemessenen Bedingungen weder ein Glycin- Betain-Transporter noch ein Cholin-Transporter in M. mazei ist. Diese Beobachtungen belegen eindeutig, dass Ota der einzige funktionelle Glycin-Betain-Transporter in M. mazei ist, während die Rolle von Otb bislang noch ungeklärt ist. 7. Nε-Acetyl-ß-Lysin, das dominante kompatible Solut in M. mazei bei 800 mM NaCl, wird durch die Enzyme AblA, einer Lysin-2,3-Aminomutase und AblB, einer ß-Lysin- Acetyltransferase synthetisiert. In dieser Arbeit wurde eine Δabl::pac-Mutante generiert, um die Fragen zu klären, ob die beiden Enzyme vom postulierten abl-Operon kodiert werden und wenn ja, welchen Phänotyp eine Nε-Acetyl-ß-Lysin-freier-Mutante bei Salzstress zeigt. NMR-Analysen zeigten, dass in der abl::pac-Mutante kein Nε-Acetyl-ß-Lysin mehr nachweisbar war. Dies belegt, dass die Gene ablA und ablB und deren Genprodukte für die Synthese von NE-Acetyl-ß-Lysin in M. mazei essentiell sind. Unter Hochsalzbedingungen ist das Wachstum von M. mazei abl::pac im Vergleich zum Wildtyp deutlich verlangsamt. Dieses Ergebnis war unerwartet, da eine abl::pac-Mutante von Methanococcus maripaludis unter Hochsalzbedingungen nicht mehr wachsen konnte. Unter Niedrigsalz und bei intermediären Salzkonzentration war das Wachstum von M. mazei abl::pac nicht eingeschränkt und verhielt sich wie der Wildtyp. In Gegenwart von Glycin-Betain akkumulierte die abl::pac-Mutante von M. mazei unter Hochsalzbedingungen 2,4 mal mehr Glycin-Betain als der Wildtyp, um das Defizit im Solutepool auszugleichen und Wachstum bei Hochsalz zu ermöglichen. Dadurch war sie in der Lage, wieder wie der Wildtyp zu wachsen. 8. Der Verlust von NE-Acetyl-ß-Lysin wurde unter Hochsalzbedingungen durch erhöhte Konzentrationen an Glutamat und einem neuen kompatiblen Solut kompensiert. NMRAnalysen zeigten, dass es sich hierbei um Alanin handelte. Bis jetzt wurde die Verwendung von Alanin als kompatibles Solut noch nie beschrieben. Um sicherzustellen, dass Alanin als kompatibles Solut in M. mazei abl::pac dient, wurde die Konzentration bei verschiedenen Salzkonzentrationen gemessen. Die Konzentration an Alanin nahm mit steigender Salzkonzentration zu. Bei 800 mM NaCl war die Konzentration 12 fach erhöht verglichen mit der Konzentration bei 400 mM NaCl. Außerdem redzierte Glycin-Betain die Alanin- Konzentration bei 800 mM NaCl um 58%. Transportexperimente zeigten, dass M. mazei kein Alanin aus dem Medium aufnehmen kann. 9. Erste Analysen möglicher Synthesewege für Alanin zeigten, dass die Alanin- Dehydrogenase nicht auf Transkriptebene unter Hochsalzbedingungen induziert war und somit keine Rolle in der Synthese von Alanin als kompatibles Solut spielen dürfte. Es könnten jedoch Aminotransferasen eine Rolle bei der Biosynthese von Alanin spielen. Des Weiteren sind die Enzyme, die für die Synthese von Glutamat als kompatibles Solut verantwortlich sind, unbekannt. Dies gilt für alle bis jetzt untersuchten Organismen, die Glutamat als kompatibles Solut nutzen. In dieser Arbeit wurde versucht, mit Hilfe der abl::pac-Mutante, die erhöhte Glutamat-Mengen zum Osmoschutz produziert, der Frage nachzugehen, welche Gene/Enzyme eine Rolle spielen könnten bei der Synthese von Glutamat als kompatibles Solut. Dazu wurden unter Hochsalzbedingungen die Transkriptmengen verschiedener Genen, die an der Glutamat-Synthese beteiligt sein könnten, in der Mutante und im Wildtyp untersucht. Hierbei zeigte sich, dass mehrere Gene verschiedener Enzyme unter Hochsalzbedingungen in der Mutante leicht induziert waren. Eines dieser Enzyme ist die Glutaminsynthetase. Dieses Enzym ist für die Umsetzung von Glutamat zu Glutamin unter Verbrauch von ATP verantwortlich. M. mazei besitzt zwei Gene, die für eine putative Gluaminsynthetase kodieren. In M. mazei abl::pac ist unter Hochsalzbedingungen das Gen glnA2 im Vergleich zum Wildtyp (4,03 ± 1,14) leicht induziert (7,63 ± 2,2). Des weiteren konnte in der Mutante eine leichte Induktion von gltB1, gltB2 und gltB3 unter Hochsalz beobachtet werden. Diese Gene kodieren für die einzelnen Domänen einer Glutamatsynthase. Diese ersten Analysen geben einen Hinweis darauf, dass die Synthese von Glutamat als kompatibles Solut über eine gekoppelte Reaktion der Glutaminsynthetase und der Glutamatsynthase verlaufen könnte.
Contents: Foreword I. Prolonged Diving Previous Investigations Present Investigations Diving Experiments with Seals Diving Experiments with a Beaver Investigations on Whales Diving Experiments with Penguins and Domestic Ducks II. Deep Diving Previous Investigations and Views Present Investigations Methods References Appendix (Tables)
The first key is completed for the Palaearctic Pristiphora Latereille, 1810 species. Pristiphora araratensis sp. n. is descdbed. Pristiphora kamtchatica Malaise, 1931, Pristiphora mesatlantica Lacourt, 1976 and Pristiphora amelanchieris (Takeuchi, 1922) are new synonyms of Pristiphora insularis Rohwer, 1910.
A survey of the freshwater fishes of the Sepik River system of northern Papua New Guinea was undertaken by the authors between 1978 and 1985 with the use of gill nets and rotenone, and also by monitoring catches at local villages and markets. We also include records of past expeditions, namely that of the Dutch naturalist Gjellerup in 1910 and the yacht Illyria in 1929. The total known freshwater fauna as reported herein consists of 57 species in 35 genera and 23 families. The fauna is typical of other sections of New Guinea and northern Australia in that it is dominated by catfishes (Ariidae and Plotosidae), rainbow fishes (Melanotaeniidae), gudgeons (Eleotrididae) and gobies (Gobiidae) which collectively comprise 57 percent of the total species. With the exception of 22 widely distributed species that are frequently estuarine dwellers and are confined to the lower Sepik, the fishes are strongly endemic, either to the Sepik-Ramu drainages (which interconnect during Doods), or the "intermontane trough" composed of the combined Markham, Ramu, Sepik, and Mamberamo systems. Individual accounts, including brief descriptions and information pertaining to habitat, distribution and biology are included for each species. In addition illustrations are provided for many of the endemic species.
Presented herein is the first morphological analysis of turtle relationships to examine the monophyly of many turtle groups by using only single species as terminals and by integrating a large number of primitive fossil taxa. The data matrix consists of 136 osteological parsimony informative characters with 169 derived character states for 45 fossil and 22 living species of the clade TESTUDINATA. The results corroborate the monophyly of a large number of previously hypothesized clades, but refute the accepted hypothesis regarding the basal split of living turtles. In particular, the primitive turdes Proterochersis robusta, Kayentachelys aprix, Mongolochelys efremovi, Meiolania platyceps, and Kallokibotion bajazidi are removed from their current position as crown turtles and placed along the phylogenetic stem of this clade. The age of the turtle crown is thereby adjusted from the Late Triassic to the Late Jurassic, which is relevant to testing molecular clock hypotheses. This revised topology has important implications for the evolution of several character complexes, because it implies that the common ancestor of all living turtles must have had a partially braced brain case and a primitive trochlear mechanism. Other noteworthy conclusions include the tentative exclusion of protostegids from CHELONIOIDEA, the placement of Platysternon megacephalum outside of CHELYDRIDAE, and the tentative interpretation of Sandownia harrisi as a basal eucryptodire.
This checklist of the lichens and Iichenicolous fungi of Chile (including the Antarctic ten-itory, Juan Fernandez and Easter island) includes 1415 taxa in 304 genera of which 1383 are lichens (in 281 genera), and 32 are lichenicolaus fungi (in 23 genera). Full bibliographic citations are given for both accepted taxa and for synonyms and references to relevant literature are included for most genera. The following new combinations are proposed: Caloplaca austroshetlandica (Zahlbr.) D.J. Galloway & Quilhot, Dendriscocaulon calithamnion (Taylor) D.J. Galloway & Quilhot, Neuropogon durietzii (Motyka) D.J. Galloway & Qllilhot, Neuropogon patagonicus (F.J. Walker) DJ. Galloway & Quilhot, and Neuropogon subamarcticus (F. J. Walker) D.,T. Galloway & Quilhot.
Taxonomic diversity of European Cottus : with description of eight new species (Teleostei: Cottidae)
(2005)
The taxonomy of European species of Coitus (Cottidae) is revised. Results of molecular studies are summarised and the variability of morphological characters is reviewed. Molecular and morphological data support the recognition of 15 diagnosable species in Europe. A neotype is designated for C. gobio; the type locality is in the lower Elbe drainage. Coitus gobio, C. hispaniolensis, C. koshewnikowi, C. microstomus, C. petiti, and C. poecilopus are re-diagnosed. Eight new species are described. Three of them are restricted to France: C. aturi to the Adam drainage, C. duranii to the upper Dordogne, upper Lot and upper Loire drainages, and C. rondeleti to the Herault drainage. Two new species are described from the Atlantic and North Sea basins: C. perifretum from Great Britain, and the ScheIdt, Rhine, Seine, lower Loire and lower Garonne drainages, and C. rhenanus from the Meuse and lower and middle Rhine drainages. Coitus scatul'igo is described from a single spring in northeastern Italy. In the Danube drainage, C. mctae front the upper Save and C. transsilvaniae from the upper Arges are distinguished from the widespread C. gobio. Lectotypes are designated for C. ferrugineus and C. pellegrini. Coitus kosllewnikowi Gratzianow, 1907 is declared nomel1 protectum and C. gobio microcephalus Kessler, 1868 is declared nomen oblitum. The original spelling of C. milvensis is discussed.
Paleogeographical, morphological, ecological, physiological, linguistic, archaeological and historical evidence is used to explain the origin and history of the domestication of the wild common carp. The closest wild ancestor of the common carp originated in the drainages of the Black, Caspian andAral seas and dispersed west as far as the Danube River and east into Siberia. The common carp today is represented by the uncertain east Asian subspecies Cyprinus carpio haematopterus and by the European Cyprinus carpio carpio. There is some reason to think that Romans were the first to culture carp collected from the Danube, and that the tradition of the "piscinae dulces" was continued in monasteries throughout the Middle Ages. We have much better documentation of carp culture in ponds of lay and clerical landowners in western Europe after the 11 th century. Distribution of the common carp west of the Danube's piedmont zone was clearly brought about by humans, as was its introduction throughout the continents. Some domestication in China may have occurred independently of similar activities in Europe, but most of the modern-day activities with the common carp in far east Asia are restricted to the domesticated common carp imported from Europe, or at best to hybrids of local and imported strains. The xanthic (red) common carp seem to have first appeared in early cultures of Europe, China and Japan but reached their fame through recent artificial selection of multicolored aberrants in Niigata Prefecture of Japan. In monetary value, production of the colored carp - the Japanese "nishikigoi" - now exceeds the production of carp as human food. As "swimming flowers" nishikigoi delight modem people as much as the taste of carp may have delighted the Romans and medieval folks at the beginning of carp domestication. The common carp is not only the most important domesticated fish but contributes over I million metric tons to world aquaculture. The surviving wild forms of the common carp are threatened or close to the fate of the aurochs, the ancestor of cattle, which became extinct in 1627.
This list of microscopic features for hardwood identification is the successor to the "Standard List of Characters Suitable For Computerized Hardwood Identification" published in 1981 (IAWA Bulletin n.s. 2: 99-145) with an explanation of the coding procedure by R.B. Miller. The 1981 publication greatly stimulated international exchange of information and experience on characters suitable for hardwood identification, and inspired considerable debate on the most desirable coding procedures and identification programs. Therefore, at the IA W A meeting during the XIV International Botanical Congress in Berlin, July 1987, it was decided to revise the 1981 standard list. Because of the continuing developments in computer technology and programming, it was agreed to limit the scope of the new list to definitions, explanatory commentary, and illustrations of wood anatomical descriptors, rather than concentrate on coding procedures. A new Committee was appointed by the IA W A Council to work towards the new list, and thanks to a substantial grant from the USDA Competitive Research Grants - Wood Utilization Program (Grant No. 88-33541-4081), a workshop was held by the Committee from October 2-7, 1988, in the Department of Wood & Paper Science, North Carolina State University, Raleigh, NC, USA, under the joint auspices of IA WA and IUFRO Division S. A preliminary list was prepared during the workshop. IA W A members were invited to comment on this list, and these comments helped with the final preparation of the new list. The list presented here was agreed to after review of subsequent drafts and extensive internal consultation between committee members. Although this list has 163 anatomical and 58 miscellaneous features, it is not a complete list encompassing all the structural patterns that one can encounter in hardwoods. Instead it is intended to be a concise list of features useful for identification purposes. Also, the numbers assigned to each feature in the present list are not meant to be codes for a computer program, but are intended to serve for easy reference, and to help translate data from one program/database to another. Wood and wood cells are biological elements, formed in trees, shrubs, and climbers to fulfill a physiological or mechanical function. Although there is more discrete diversity in wood structure than in many other plant parts, there is also much continuous variation, and any attempt to classify this diversity into well-defined features has an artificial element. Yet we are confident that in the feature list presented here ambiguity of descriptors has been limited to a minimum, and we hope that all present and future colleagues engaged in wood identification and descriptive wood anatomy will find this list a valuable guide and reference.
I conducted an 18 month study on the behavior and ecology of two species of sympatric caviid rodents (Kerodon rupestris and Galea spixii) in northeastern Brazil. Preliminary observations indicated that Kerodon was a habitat specialist. occurring only in large boulder piles. whereas Galea appeared to be a habitat generalist. occurring in a variety of open habitats excepting the boulder piles inhabited by Kerodon. This situation presented an ideal field experiment to compare the social structures in these two closely related genera. I first established breeding colonies of both in order to describe their behavioral displays and to discern their function. Complete behavioral repeltoires. including vocalizations. are presented for both Kerodon and Galea. Reproduction and growth. behavioral development. sexual behavior. agonistic behavior. and use of space were all examined both quantitatively and qualitatively in the colonies and in the field. Time budgets were calculated and analyzed for both genera. Differences in rates of growth and behavioral development between the two genera afe probably related to ecological aspects of their significantly different microhabitat preferences. Data on sexual and agonistic behavior collected in the colonies suggested that Kerodon exhibited resource defense polygyny, whereas the Galea mating system approximated male dominance polygyny. Field data supported the colony observations. These differences in mating systems may be related to the different habitat preferences observed. Kerodvll is compared to other resource defense polygynists. Finally, a model for the evolution of behavior in the family Caviidae is presented. The social organizations of the various genera seem to be very responsive to ecological requirements. The importance of social organization in ecological adaptation is discussed.
Maintenance of genomic integrity is essential to avoid cellular transformation, neoplasia, or cell death. DNA synthesis, mitosis, and cytokinesis are important cellular processes required for cell division and the maintenance of cellular homeostasis; they are governed by many extra- and intra-cellular stimuli. Progression of normal cell division depends on cyclin interaction with cyclin-dependent kinases (Cdk) and the degradation of cyclins before chromosomal segregation through ubiquitination. Multiple checkpoints exist and are conserved in the cell cycle in higher eukaryotes to ensure that if one fails, others will take care of genomic integrity and cell survival. Many genes act as either positive or negative regulators of checkpoint function through different kinase cascades, delaying cell cycle progression to repair the DNA lesions and breaks, and assuring equal segregation of chromosomes to daughter cells. Understanding the checkpoint pathways and genes involved in the cellular response to DNA damage and cell division events in normal and cancer cells, provides information about cancer predisposition, and suggests design of small molecules and other strategies for cancer therapy. Key Words: ATM-ATR; ATM/ATR; Aurora kinases; BRCAl; Cdc6; Cdc25; Cdc27-Cdc20/CdhI; Cell cycle; CENP-E; centrosome; checkpoint; Chkl/Chk2; cyc1in-Cdk; cyclindependent kinase inhibitors (CKI); hATRIP; Mad/Bub; MCM; MgcRacGAP; microtubule-associated proteins (MAPs); mitotic exit network (MEN); Mpsl; NIMA kinases; ORC; p53; PCNA; PBK-Akt; Plk; Rad50-Nbsl-Mrell; Ran-GTP; Ras; RB-E2F; SMC; Teml.
Twelve genera, two of them new, are recognized in the tribe Adesmiini in southern Africa. Four new species of Epiphysa, one of Alogenius (placed in a new subgenus), two of Stenocara, one of Metriopus, and one placed in one of the new genera, are described. The genera are revised, and their distribution and relationship are briefly discussed
The former and current distribution of the quokka, Setortix brachyurus, was mapped from published and all available unpublished records. At the time of European settlement the quokka was widespread and abundant and its distribution encompassed an area of approximatelyThe former and current distribution of the quokka, Setortix brachyurus, was mapped from published and all available unpublished records. At the time of European settlement the quokka was widespread and abundant and its distribution encompassed an area of approximately 41 200 km2 of south-west Western Australia inclusive of two offshore islands, Bald Island and Rottnest Island. Historical reports indicated an extensive population decline occurred in the 1930s. The decline continued, with a previously undocumented decline apparent in the period from 1980 to 1992. However, this decline may be an artefact of the time scales used for mapping and may well equate with a previously reported decline lor a suite of south -west mammals in the 1970s. By 1992 the quokka´s distribution had been reduced to an area of approximately 17800 km2. An increased awareness of the presence of the quokka on the mainland has resulted in numerous reportings of quokka presence since 1992, has confimled the existence of several populations at the northern extent of the quokka´´s known geographic range and indicated the cmrent, 2005, distribution to be similar to that in 1992. However, survey and population estimates at six of these mainland locations from the northem jarrah forest indicated low abundance. There have been no population estimates elsewhere on the mainland. Two populations have been reported tiom the Swan Coastal Plain, but neither has been confirmed extant. Predation by the introduced fox, Vulpes vulpes, is implicated as a major cause of the quokka´s initial decline, while ongoing predation, habitat destruction and modification through altered tire regimes have contributed to the continued decline. Specific conservation management actions are recommended, namely: (i) Implementing an active adaptive management program in the northern jarrah forest to determine quokka population response to habitat manipulation through the use of fIre, fox baiting and pig control; (ii) Surveying the Stirling fumge and Green Range populations with emphasis placed on determining population size and population genetic structure; (iii) Surveying the reported occurrences from the Swan Coastal Plain, with emphasis on unambiguously determining presence. If confirmed, priority should he directed to assessing population size and determining the management requirements to ensure persistence of the population; (iv) Surveying southem forest and south coast populations to assess quokka population size, the extent of movement between sllbpopulations and assessment of the range of habitat types used by quokkas. The latter should be combined with spatial analyses of known extant populations and suitable and potentially suitable habitat; (v) Determining the role of tire in establishing and maintaining preferred habitat of southern forest and south coast populations; and (vi) Establishing a program to assess the potential effects from management operations.
Total body water increases in pregnancy and while the uterus, placenta, fetus, and amniotic fluid constitute part of this increase, the largest component is in the extracellular water. Fat stores also increase and thus the distribution volumes of all drugs expand, but the major effect is seen in polar drugs which are confined to the extracellular space. Cardiac output and renal function also increase and elimination of polar drugs is acelerated. In contrast, the elimination of lipophilic drugs may be retarded, and the effect on intermediate drugs is variable. Polar drugs cross the placenta slowly and accumulate in amniotic fluid and therefore in the fetal gut lumen. Lipophilic drugs cross the placenta rapidly and their transplacental distribution is dependent on relative maternal and fetal affinity: this is determined largely by protein binding on either side of the placenta. The. fetus and neonate dispose of all drugs less rapidly than adults, the most efficient elimination processes being sulphate conjugation and renal excretion.
A skeletal world revision of the genus is presented to accompany a family account for Flora Malesiana. 82 species are recognised, of which 74 occur in the Malesiana region. Six species are desctibed as new, one species is raised from infraspecific status, and five species are restored from synonymy. Many names are typified for the first time. Three widespread, or locally abundant hybrids are also included. Full descriptions are given for new (6) or recircumscribed (7) species, and emended descriptions of species arc given where necessary (9). Critical notes are given for all the species. Little known and excluded species are discussed. An index to all published species names and an index of exsiccatae is given.
Through the kind assistance of O. G. Lloyd of Cincinnati, Ohio, most of the Australian polypores in our possession have been accurately identified. In the present paper we record our various collections. In doing so, we make use of the excellent keys employed by Lloyd in the following works: "Synopsis of the Genus Hexagona" (Ohio, 1910), "Synopsis of the Stipitate PoIyporoids" (Ohio, 1912), "Synopsis of the Section Apus of the Genus Polyporus" (Ohio, 1915) and "Synopsis of the Genus Fomes" (Ohio, 1915). In addition to recording the plants we have handled, we have included as well all the Australian species embraced in these works. Australian mycologists should thus have available a workable scheme for the identification of most of our firmer polypores. Those who have attempted to work out the species from Cooke´s "Handbook of Australian Fungi", will appreciate the value of Lloyd´s work. We deal first with the Stipitate Polypores, then with Fomes, Polyporus (Apus) and Hexagona.
In this thesis I have investigated the regulation of eicosanoid synthesizing-enzymes by cannabinoid receptor agonists. Rat renal mesangial cells were used as a model system. I could show that all three (CB1, CB2, and GPR55) cannabinoid receptors are expressed on the mRNA level in rat renal mesangial cells – but with differing expression profiles. The CB1 and GPR55 receptors are expressed in comparable amounts, whereas the CB2 receptor is considerably less expressed than the CB1 and the GPR55 receptors. Furthermore I could show that stimulation of renal mesangial cells with CB1 receptor agonists, such as R(+)MA or ACEA, increased IL-1β-induced cPLA2, sPLA2-IIa, and COX2 protein and mRNA expression which subsequently led to an enhanced IL-1β-induced PGE2 formation. Additionally, the IL-1β- induced sPLA2-IIa promoter activity was also increased by CB1 receptor stimulation. Besides the modulated expression of the eicosanoid synthesizing enzymes, I could show that CB1 agonists also led to an increase of IL-1β-induced iNOS expression and subsequent NO formation. In contrast, stimulation with CB2 selective agonists led to a decrease in IL-1β- induced sPLA2-IIa protein expression and PGE2 formation. Accordingly, the IL-1β-induced sPLA2-IIa promoter activity was also reduced by CB2 receptor agonists. IL-1β-induced iNOS expression and subsequent NO formation were not influenced by CB2 recptor activation. Matching the results I obtained with CB1 receptor agonists on IL-1β-induced PGE2 formation, I could observe an increased cPLA2 protein and mRNA expression with a subsequent increase in IL-1β-induced PGE2 formation by GPR55 stimulation. Stimulation with THC, an unselective CB agonist, increased the IL-1β-induced sPLA2-IIa protein expression and subsequently led to an enhanced IL-1β-induced PGE2 formation. Subjecting the cells to higher THC concentrations surprisingly led to a reduction of the IL-1b-induced sPLA2-IIa protein expression and PGE2 formation. A possible explanation may be the differential expression of the three CB receptors. At low concentrations THC may predominantly activate CB1 and GPR55 and with increasing concentration CB2 receptors may also be activated, slightly reversing the enhancing effect. Moreover, I could show that the CB1 receptor stimulation mediated phosphorylation and hence the activation of ERK1/2 MAPK. Additionally to ERK1/2, there was also a phosphorylation and activation of NFkB observed by CB1 receptor stimulation. In my thesis I could show for the first time that PPARα was activated by IL-1β in rMC. The IL-1β-induced PPARα promoter activity was completely inhibited by addition of the CB2 receptor agonist, JWH015. These findings were confirmed by inhibition of the IL-1β-induced PGE2 formation by a PPARα antagonist (MK-886). In summary, I could show that activation of CB1 receptors in our system led to a worsening of an inflammatory condition, whereas activation of the CB2 receptors led to the complete opposite; namely a reduction of the inflammatory response by reducing the sPLA2-IIa expression and PGE2 formation. GPR55 activation did not display any alteration of inflammatory conditions, since the classical inflammatory pathway was not influenced.
This synonymic list of the flat bugs (Aradidae) ofthe world enumerates 1,798 species in 211 genera. Names of eight fossil species are given in their original combination in modern genera. The list is introduced by brief discussions of habits, food, ecology and distribution. Many taxonomic innovations are included, as follows: Subfamily Chinamyersiinae is divided into two new tribes, Chinamyersiini and Tretocorini; the subfamily Prosympiestinae is divided into two new tribes, Llaimacorini and Prosympiestini. All currently recognized subgenera are raised to generic rank: Aneurillus, Breviscutaneurus, lralunelus, and Paraneurus from Aneurus; Miraradus and Quilnus from Aradus; Lissaptera and Nesiaptera from Acaraptera; Neoproxius and Nesoproxius from Proxius (see list below for new combinations resulting). Three genus-group names are raised from synonymy: Aneurosoma; Burgeonia and Brachyrhynchus. One genus-group name is reduced to synonymy; Zimera as a junior synonym of Brachyrhynchus. The following new species-genus combinations are made, these mostly resulting from elevation of subgenera to generic status or species transfers. In Aneurillus - borneensis, cetratus, cheesmanae, consimilis, doesbergi, foliaceus, glaberrimus, gracilis, jacobsoni, longicollis, papuasicus, pumilus, superbus; in Aneurosoma - dissimile; in Aneurus - septentrionalis; in Aradus - dignatus; in Arbanatus - asiaticus, loriae; in Brachyrhynchus - affinis, amplicollis, andamanensis, angolensis, armigerus, australis, bergrothi, bergrothianus, bhoutanensis, breuiceps, burmensis, confectus, confusus, consimilis, crenatus, dentipes, discrepans, dispar, duboisi, elegans, exarmatus, funebrus, furcatulus, furcatus, germari, gracilicornis, granos us, hospidus, hoberlandti, horridus, hsiaoi, incisus, incognitus, insignis, intermedius, javanensis, kachenensis, kerzhneri, lindemannae, longicornis, longirostris, luberoensis, luzonicus, machadoi, madagascariensis, mauricii, membranaceus, micronesicus, monedulus, mario, ouerlaeti, parallelus, pauper, philippinensis, piliferus, poriaicolus, projectus, quadridentatus, quadrispinosus, rossi, rugosus, scrupulosus, serratus, similis, solomonensis, spinipes, stolidus, subinermis, subtriangulus, sulcatus, sulcicornis, sumatrensis, taiwanicus, teter, thailandicus, triangulus, tristis, urijdaghi; in Breviscutaneurus - breviscutatus, helenae, madagascariensis, medioscutatus; in Burgeonia - burgeon, dilatatus, froidebisei, intermedius, kormileui, madagascariensis, maynei, paruus, schoutedeni, usingeri; in Chiastoplonia - pusio; in lralunellus - aibonitensis, bergi, bispinosus, boliuianus, carioca, costariquensis, flavomaculatus, ftitzi, gallicus, leptocerus, longicornis, marginalis, monrosi, plaumanni, politus, sahlbergi, simulans, subdipterous, tenuis, westwoodi, wygodzinsky; in Miraradus - foliaceus, himalayensis, mirabilis, oeruendetes; in Neoproxius - amazonicus, carioca, costariquensis, gypsatus, incaicus, lindemannae, magdalenae, nicaraguensis, palliatus, panamensis, personatus, peruuianus, schwarzii; in Nesiaptera - denticulata, gibbosa, ouata, rotundata, tuberculata, zimmermani; in Nesoproxius - angulatus, constrictus, gracilis, hexagonalis, malayensis, minutus, punctulatus, vietnamensis, yoshimotoi; in Neuroctenus - ghesqueri; in Oreossa - insignis; in Quilnus - amurensis, breuirostris, discedens, heidemanni, niger, nigrinus, oregonicus, paruicollis, subsimilis, usingeri. Three new species names are proposed: Brachyrhynchus pauper for the preoccupied Mezira modesta Kormilev, 1972; Mezira uicina for the preoccupied Mezira proxima Kormilev, 1982; and Mezira doesburgi for the preoccupied Mezira surinamensis Kormilev, 1974. Five new species-synonymys are made: Aradus centriguttatus as a junior synonym of Aradus similis; Mezira jacobsoni as a junior synonym of Daulocoris cornigerus; Mezira modesta as a junior synonym of Brachyrhynchus membranaceus; Neuroctenus breuicornis as a junior synonym of Neuroctenus ater; Notoplocaptera malaisei as a junior synonym of Zoroaptera malaisei. Four new emendations of gender endings are proposed for the species name "halaszfyi": Artabanus halaszfyae, Chelysosoma halaszfyae, Ctenoneurus halaszfyae, Mezira halaszfyae.
The research presented in this thesis characterizes U2AF homology motifs (UHM) and their interactions with UHM ligand motifs (ULM) in the context of splicing regulation. UHM domains are a subgroup of RNA recognition motifs (RRM) originally discovered in the proteins U2AF65 and U2AF35. Whereas canonical RRMs are usually involved in binding of RNA, UHM domains bind tryptophan containing linear protein motifs (ULM) instead. In the first article, we analyze the complex network of interactions between splicing factors and RNA that initiate the assembly of the spliceosome at the 3´ splice site of an intron. The protein U2AF65 binds a pyrimidine-rich element in introns and recruits U2snRNP by binding its protein component SF3b155. My contribution was to define the binding site of the protein U2AF65 to the intrinsically unstructured N-terminus of the scaffolding protein SF3b155. I could show that the UHM domain of U2AF65 recognizes a ULM in SF3b155, and that this binding site is not overlapping with the binding sites of other splicing factors, like p14, to SF3b155. As the U2AF65-UHM:SF3b155-ULM interaction is mutually exclusive with an interaction between U2AF65-UHM and a ULM in the splicing factor SF1, which was reported to initially recognize the branch point sequence, my results provide the molecular details on how SF3b155 replaces SF1 during spliceosomal reorganizations. In the second article, we show that overexpression of the UHM domain of the splicing factor SPF45 induces exon 6 skipping in the pre-mRNA of Fas (CD95/APO-1). I provide evidence for in vitro binding of SPF45-UHM to ULM sequences in the splicing factors U2AF65, SF1, and SF3b155. I crystallized free and SF3b155-bound SPF45 UHM and solved both structures by X-ray crystallography. The analysis of the complex interface and sequence differences in the ULMs allowed me to design mutations of SPF45-UHM, which selectively inhibit binding to distinct ULMs. After assessing the ULM binding properties in vitro, we could show that the activity of SPF45-UHM in influencing the splicing pattern of Fas relies on interactions with SF3b155 and/or SF1, but that an interaction with U2AF65 is dispensable. A mechanism for the activity of SPF45-UHM could thus be engaging in ULM interactions and thus interfering with the network of interactions that initiate the assembly of the spliceosome at the 3´splice site, as described above. In the third article, we describe an unusual flexible homodimerization mode of the UHM in the splicing factor Puf60, which enables simultaneous interactions with ULM sequences on other splicing factors. I could show that the NMR relaxation properties of Puf60-UHM are inconsistent with a model of a rigid dimer, but rather indicate a dimerization via a flexible linker. I identified a flexible loop in the peptide backbone of Puf60-UHM, and showed that mutiation of acidic residues in this loop impairs the dimerization. To analyze the dimerization interface in further detail, I solved the structure of Puf60-UHM by X-ray crystallography. The acidic residues in the flexible loop of one UHM dimer subunit mediate the dimerization by contacting basic residues on the β-sheet surface of the other dimer subunit. Differences in the four dimer interfaces observed for the eight molecules in the asymmetric unit of the crystal support the model of an undescribed, flexible mode of dimerization, and thus complement the NMR relaxation data. Furthermore, I could show that the Puf60-UHM dimer and U2AF65-UHM contact different ULM sequences on the SF3b155 N-terminus in vitro, thus providing a possible explanation for the mutual cooperative activation of Puf60 and U2AF65 in splicing assays described in the literature. The fourth article is a review about recent research on the recognition of DNA double strand breaks (DSB) by covalent histone modifications. The p53 binding protein 1 (53BP1) is a DSB sensor and a checkpoint protein for mitosis. Recent crystallographic evidence indicates that 53BP1 recognizes DSB sites by binding histone H4 dimetylated at lysine 20 (H4-K20). We provide a comprehensive overview of the atomic resolution structures that revealed how proteins can specifically recognize histone tail modifications, especially methylated lysines, to read the information stored in what is called the histone code.
The specimens which form the basis of the following notes and descriptions were received by the writer from Mr. Ch'i Ho, Asistant Entomologist of Fan Memorial Institute of Biology, who collected thern either in Peiping or Eastern Tomb (40.2 N, 117.0 E), Hopei Province. They belong to nineteen species and are included in fifteen genera. Two of the species are believed to be new to science.
A cladistic analysis is presented of the hawkmoths of the tribe Acherontiini, Morgan´s Sphinx (Xanthopan morganii (Walker», and related genera. The study aims to test the monophyly of tribe Acherontiini; the hypothesis that all taxa with extremely long probosces (some Acherontiini, Meganoton rubescens, Neococytius, Xanthopan) form a monophyletic group, or at least fall within a single reasonably compact clade; and, within this group, to determine whether Xanthopan is more closely related to Acherontiini or to COCytillS and Neococytius. The data set comprises 109 characters derived from adult and immature stage morphology, biology and behaviour. These data were analysed using equal weighting, successive approximations character weighting (SACW) and implied weighting. All weighting schemes agreed on the monophyly of Acherontiini and of a group of genera comprising Amphimoea, Cocytius and Neococytius (the Cocytius group). Several other generic and suprageneric clades were also consistently recovered. However, those hawkmoths with extremely long probosces were never recovered as a monophyletic group. The relationships of Xanthopan were also ambiguous. Equal weighting and SACW placedXanthopan + Meganoton rztbescens (Butler) as sister to the COCytills group, while implied weighting placed Xanthopan as sister to Acherontiini. This latter relationship is based primarily on shared possession of a pilifer/palp hearing organ. Further analyses suggested the two components of this organ were not biologically independent. Downweighting this feature accordingly resulted in all weighting schemes converging on the topology found by equal weighting. Exclusion of the incomplete subset of immature stage data had no effect under implied weighting but equal weighting and SACW now recovered a Neotropical clade comprising Manduca. and the Cocytius group, while Xanthopan was placed with M. rubescens and Panogena. Downweighting the pilifer/palp hearing organ under implied weighting again caused convergence with the equal weighting/SACW results. Thus, the relationships of Xanthopan remain equivocal and further data, particularly from the immature stages, will be required to elucidate its phylogenetic position further.
Keys to the hairs of 44 species of southern African Cricetidae and Muridae have been devised for the identification of these species. The keys are based primarily on the cuticular scale patterns and groove characters. Distribution data and descriptions of the hairs are presented with micrographs to assist in identification.
Reggie-1 (flotillin-2) and reggie-2 (flotillin-1) are membrane microdomain proteins which are associated with the membrane by means of acylation. They influence different cellular signaling processes, such as neuronal, T-cell and insulin signaling. Upon stimulation of the EGF receptor, reggie-1 becomes phosphorylated and undergoes tyrosine 163 dependent translocation from the plasma membrane to endosomal compartments. In addition, reggie-1 was shown to influence actindependent processes. Reggie-2 has been demonstrated to affect caveolin- and clathrin-independent endocytosis. Both proteins form homo- and hetero-oligomers, but the function of these oligomers has remained elusive. Moreover, it has not been clarified if functions of reggie-1 are also influenced by reggie-2 and vice versa. The first aim of the study was to further investigate the interplay and the heterooligomerization of reggie proteins and their functional effects. Both reggie proteins were individually depleted by means of siRNA. In different siRNA systems and various cell lines, reggie-1 depleted cells showed reduced protein amounts of reggie-1 and reggie-2, but reggie-2 knock down cells still expressed reggie-1 protein. The decrease of reggie-2 in reggie-1 depleted cells was only detected at protein but not at mRNA level. Furthermore, reggie-2 expression could be rescued by expression of siRNA resistant wild type reggie-1-EGFP constructs, but not by the soluble myristoylation mutant G2A. This mutant was also not able to associate with endogenous reggie-1 or reggie-2, which demonstrates that membrane association of reggie-1 is necessary for hetero-oligomerization. In addition, fluorescence microscopy studies and membrane fractionations showed that correct localization of overexpressed reggie-2 was dependent on co-overexpressed reggie-1. Thus, hetero-oligomerization is crucial for membrane association of reggie-2 and for its protein stability or protein expression. Moreover, the binding of reggie-2 to reggie-1 required tyrosine 163 of reggie-1 which was previously shown to be important for endosomal translocation of reggie-1. Since reggie-2 was implicated to function in clathrin- and caveolin-independent endocytosis pathways, the effect of reggie-2 depletion on reggie-1 endocytosis was investigated. Indeed, reggie-1 was dependent on reggie-2 for endosomal localization and EGF-induced endocytosis. By FRET-FLIM analysis it could be shown that reggie heterooligomers are dynamic in size or conformation upon EGF stimulation. Thus, it can be concluded that reggie proteins are interdependent in different aspects, such as protein stability or expression, membrane association and subcellular localization. In addition, these results demonstrate that the hetero-oligomers are dynamic and reggie proteins influence each other in terms of function. A further aim was the characterization of reggie-1 and reggie-2 function in actindependent processes, where so far only reggie-1 was known to play a role. Depletion of either of the proteins reduced cell migration, cell spreading and the number of focal adhesions in steady state cells. Thus, also reggie-2 affects actin-dependent processes. Further investigation of the focal adhesions during cell spreading revealed that depletion of reggie-1 displayed different effects as compared to reggie-2 knock down. Reggie-1 depleted cells had elongated cell-matrix-adhesions and showed reduced activation of FAK and ERK2. On the other hand, depletion of reggie-2 resulted in a restricted localization of focal adhesion at the periphery of the cell and decreased ERK2 phosphorylation, but it did not affect FAK autophosphorylation. Hence, reggie proteins influence the regulation of cell-matrix-adhesions differently. A link between reggie proteins and focal adhesions is the actin cross-linking protein -actinin. The interaction of -actinin with reggie-1 could be verified by means of co-immunoprecipitations and FRET-FLIM analysis. Reggie-1 binds -actinin especially in membrane ruffles and in other locations where actin remodeling takes place. Moreover, -actinin showed a different localization pattern during cell spreading in reggie-1 depleted cells, as compared to the control cells. These results provide further insights into the function of both reggie proteins. Their interplay and hetero-oligomerization was shown to be crucial for their role in endocytosis. In addition, both reggie proteins influence actin-dependent processes and differentially affect focal adhesion regulation.