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911.
Kurt Kräuter N. N. Kartaschew G. Mauersberger Achim Bruch Wolfgang Stickel J. Werner Günther Jung Clemens Kleinsteuber J. Peitzmeier Wolfgang Makatsch G. Niethammer Max Dornbusch Ute Rahne Rudolf Berndt Gustav Laue Gottfried Vauk Felix Gräfe und H. E. Wolters 《Journal of Ornithology》1962,103(2-3):297-305
Ohne Zusammenfassung 相似文献
912.
Jennifer Groth Yesu Song Adolf Kellermann Andrea Schwarzfischer 《Journal of applied genetics》2013,54(2):169-178
Potato wart is caused by the obligate biotrophic fungus Synchytrium endobioticum, which is subject to quarantine regulations due to the production of long persisting spores in the soil and the lack of effective fungicides. The objective of this study was to identify quantitative trait loci (QTL) for resistance against potato wart races (R) 1, 2, 6 and 18 in a tetraploid potato population developed by crossing cv. Saturna (resistant to R1) with cv. Panda (resistant to R1, R2, R6, R18). A total of 92 progenies were used for phenotyping and genotyping. Resistance tests were performed for races 1 and 18 in 2 years and for races 2 and 6 in 1 year on 10 to 20 eyepieces per genotype. Based on amplified fragment length polymorphism (AFLP) and simple sequence repeat (SSR) markers, linkage maps were established for the female and male parent, respectively. Single marker analysis followed by a multiple regression analysis revealed initial marker–trait associations. The interval mapping routine of TetraploidMap was applied for QTL analysis. A major QTL for resistance against race 1 explaining between 46 % and 56 % of the phenotypic variation was identified near Sen1, a known resistance locus for potato wart race 1 on chromosome XI. Other resistance QTL were detected on chromosomes I (to R2), II (to R6, 18), VI (to R1, 2, 6, 18), VII (to R2, 6, 18), VIII (to R1, 2, 6, 18), X (to R2, 6, 18), XI (to R2, 6, 18) and on an unknown linkage group (to R18) explaining minor to moderate effects of the phenotypic variation. Resistance QTL against different potato wart races often overlapped, particularly concerning races 2, 6 and 18. Overall, this study gives a valuable insight into the complex inheritance of resistance against potato wart. 相似文献
913.
Elodie Pradines Damien Loubet Sophie Mouillet-Richard Philippe Manivet† Jean-Marie Launay†‡ Odile Kellermann Benoît Schneider 《Journal of neurochemistry》2009,110(3):912-923
Despite considerable efforts to unravel the role of cellular prion protein (PrPC ) in neuronal functions, the mechanisms by which PrPC takes part in the homeostasis of a defined neuronal phenotype remain poorly characterized. By taking advantage of a neuroectodermal cell line (1C11) endowed with the capacity to differentiate into serotonergic (1C115-HT ) or noradrenergic (1C11NE ) neurons, we assessed the contribution of PrPC to bioaminergic cell functions. We established that in 1C11-derived neuronal cells antibody-mediated PrPC ligation triggered tumor necrosis factor (TNF)-α release, through recruitement of the metalloproteinase TNF-α converting enzyme (TACE). TNF-α shed in response to PrPC acts as a second message signal, eliciting serotonin (5-HT) or norepinephrine (NE) degradation in 1C115-HT or 1C11NE cells, respectively. Our data thus introduced TNF-α as a PrPC -dependent modulator of neuronal metabolism. Of note, we previously reported on a control of neurotransmitter catabolism by 5-HT2B or α1D autoreceptors in 1C11 bioaminergic neurons, via the same TACE/TNF-α pathway (Ann. N Y Acad. Sci. 1091, 123). Here, we show that combined stimulation of PrPC and these two bioaminergic receptors add their effects on neurotransmitter degradation. Overall, these observations unveil a novel contribution of PrPC to the control of neuronal functions and may have implications regarding dysfunction of the bioaminergic systems in prion diseases. 相似文献
914.
Gottfried Wagner 《Planta》1974,118(2):145-157
Summary Some ionic relations of the filamentous green alga Mougeotia sp. have been analyzed under different light conditions. Data from influx and efflux measurements using 86Rb+ and 36Cl- fit the model of three cellular compartments (cell wall, cytoplasm, vacuole) in series. This result is remarkable, since in a Mougeotia cell at least two thirds of the cytoplasmic compartment are occupied by the cell-filling, flat and nearly rectangular chloroplast which is axially oriented. The chloroplast is concluded to be part of the cytoplasmic flux compartment.Photosynthetically saturating irradiances of continuous white light enhance the active and passive fluxes of K+ and Cl- at the plasmalemma by a factor of 3. Photosystem II is responsible for the light-dependent increase of the uptake of Cl- (36Cl-) whereas the uptake of K+ (86Rb+) depends additionally on energy from photosystem I.Ion flux measurements performed after irradiations with red and far-red, respectively, show that the fluxes of K+ and Cl- across the plasmalemma are not affected by the state of phytochrome. 相似文献
915.
The stereoselective metabolism of the former sedative thalidomide and the metabolism of its analogue EM 12 were studied in vitro with liver homogenates. In our study we focused on hydroxylated nonhydrolyzed metabolites of thalidomide. An analytical HPLC method was developed to determine these metabolites directly. The investigations showed a highly stereoselective biotransformation of thalidomide. 5-Hydroxy thalidomide was preferentially formed by (?)-(S)-thalidomide, whereas (+)-(R)-thalidomide was metabolized to two hitherto unknown compounds (Met A and B). Mass spectrometry of these metabolites Met A and B indicated that oxidation or hydroxylation took place in the glutarimide moiety. Biotransformation studies with the more stable thalidomide analogue EM 12 revealed four new metabolites (Met C? F) whose quantities differed in the selected liver homogenate. © 1994 Wiley-Liss, Inc. 相似文献
916.
917.
Gottfried Haug 《Journal of comparative physiology. A, Neuroethology, sensory, neural, and behavioral physiology》1933,19(2):246-303
Ohne Zusammenfassung 相似文献
918.
We report the preparative separation of rac-zopiclone using malic acid as the resolving agent. Furthermore, two different methods for the analytical determination of zopiclone enantiomers by HPLC on chiral stationary phases are described. The benzodiazepine receptor binding of the isolated enantiomers was investigated. Half-maximal inhibitory concentrations of (+)- and (?)-zopiclone were 21 or 1,130 nmol/liter, respectively, indicating a more than 50 times higher affinity of the (+)-enantiomer toward the receptor. © 1993 Wiley-Liss, Inc. 相似文献
919.
William Martin Katrin Henze Josef Kellermann Anke Flechner Claus Schnarrenberger 《Plant molecular biology》1996,30(4):795-805
Ribose-5-phosphate isomerase (RPI) catalyses the interconversion of ribose-5-phosphate and ribulose-5-phosphate in the reductive and oxidative pentose phosphate pathways in plants. RPI from spinach chloroplasts was purified and microsequenced. Via PCR with degenerate primers designed against microsequenced peptides, a hybridisation probe was obtained and used to isolate several cDNA clones which encode RPI. The nuclear-encoded 239 amino acid mature RPI subunit has a predicted size of 25.3 kDa and is translated as a cytosolic precursor possessing a 50 amino acid transit peptide. The processing site of the transit peptide was identified from protein sequence data. Spinach leaves possess only one type of homodimeric RPI enzyme which is localized in chloroplasts and is encoded by a single nuclear gene. Molecular characterization of RPI supports the view that a single amphibolic RPI enzyme functions in the oxidative and reductive pentose phosphate pathways of spinach plastids.Abbreviations RPI
ribose-5-phosphate isomerase
- OPPP
oxidative pentose phosphate pathway
- CNBr
cyanogen bromide
- R5P
ribose-5-phosphate
- Ru5P
ribulose-5-phosphate 相似文献
920.