TY  - JOUR
A1  - Kamjunke, Norbert
A1  - Bohn, Christiane
A1  - Grey, John
T1  - Utilisation of dissolved organic carbon from different sources by pelagic bacteria in an acidic mining lake
N2  - We compared growth rates and efficiencies of pelagic bacteria from an extremely acidic mining lake (pH 2.6, mean depth 4.6m) supplied with different sources of carbon: (1) excreted by phytoplankton, (2) derived from benthic algae, (3) entering the lake via ground water, and (4) leached from leaf litter. Bacteria exhibited high growth rate and efficiency on exudates of pelagic and benthic algae. In contrast, they showed a lower growth rate and efficiency with organic carbon from ground water, and grew at a very high rate but a very low efficiency on leaf leachate. Results from stable isotope analyses indicate a greater importance of benthic exudates and leaf leachate for bacteria in the epilimnion, and a higher impact of ground water sources in the hypolimnion. Given the magnitude of differential source inputs into the lake, we suggest that benthic primary production was the most important carbon source for pelagic bacteria. The benthic-pelagic coupling seems to be more relevant in this shallow acidic lake with low pelagic carbon dioxide concentrations than in neutral lakes
Y1  - 2006
UR  - http://www.schweizerbart.de/j/archiv-hydrobiologie/
U6  - https://doi.org/10.1127/0003-9136/2006/0165-0355
SN  - 0003-9136
ER  - 
TY  - JOUR
A1  - Kamunke, Norbert
A1  - Bohn, Christiane
T1  - Utilisation of dissolved organic carbon from different sources by pelagic bacteria in an acidic mining lake
Y1  - 2006
ER  - 
TY  - JOUR
A1  - Eccard, Jana
A1  - Dean, W. Richard J.
A1  - Wichmann, Matthias
A1  - Huttunen, S. M
A1  - Eskelinen, Eeva-Liisa
A1  - Moloney, Kirk A.
A1  - Jeltsch, Florian
T1  - Use of large Acacia trees by the cavity dwelling Black-tailed Tree Rat in the southern Kalahari
N2  - Recent extensive harvesting of large, often dead Acacia trees in and savanna of southern Africa is cause for concern about the conservation status of the arid savanna and its animal community. We mapped vegetation and nests of the Black-tailed Tree Rat Thallomy's nigricauda to assess the extent to which the rats depend on particular tree species and on the existence of dead, standing trees. The study was conducted in continuous Acacia woodland on the southern and eastern edge of the Kalahari, South Africa. Trees in which there were tree rat nests were compared with trees of similar size and vigour to identify the characteristics of nest sites. Spatial analysis of tree rat distribution was conducted using Ripley's-L function. We found that T nigricauda was able to utilize all available tree species, as long as trees were large and old enough so that cavities were existing inside the stem. The spatial distribution of nest trees did not show clumping at the investigated scale, and we therefore reject the notion of the rats forming colonies when inhabiting continuous woodlands. The selection of a particular tree as a nest site was furthermore depending on the close proximity of the major food plant, Acacia mellifera. This may limit the choice of suitable nest sites. since A. mellifera was less likely to grow within a vegetation patch containing a large trees than in patches without large trees.
Y1  - 2006
UR  - http://www.sciencedirect.com/science/journal/01401963
U6  - https://doi.org/10.1016/j.jaridenv.2005.06.019
SN  - 0140-1963
ER  - 
TY  - JOUR
A1  - VanderVen, Peter F. M.
A1  - Ehler, Elisabeth
A1  - Vakeel, Padmanabhan
A1  - Eulitz, Stefan
A1  - Schenk, Jörg A.
A1  - Milting, Hendrik
A1  - Micheel, Burkhard
A1  - Fürst, Dieter Oswald
T1  - Unusual splicing events result in distinct Xin isoforms that associate differentially with filamin c and Mena/ VASP
N2  - Filamin c is the predominantly expressed filamin isoform in striated muscles. It is localized in myofibrillar Z- discs, where it binds FATZ and myotilin, and in myotendinous junctions and intercalated discs. Here, we identify Xin, the protein encoded by the human gene 'cardiomyopathy associated 1' (CMYA1) as filamin c binding partner at these specialized structures where the ends of myofibrils are attached to the sarcolemma. Xin directly binds the EVH1 domain proteins Mena and VASP. In the adult heart, Xin and Mena/VASP colocalize with filamin c in intercalated discs. In cultured cardiomyocytes, the proteins also localize in the nonstriated part of myofibrils, where sarcomeres are assembled and an extensive reorganization of the actin cytoskeleton occurs. Unusual intraexonic splicing events result in the existence of three Xin isoforms that associate differentially with its ligands. The identification of the complex filamin c-Xin-Mena/VASP provides a first glance on the role of Xin in the molecular mechanisms involved in developmental and adaptive remodeling of the actin cytoskeleton during cardiac morphogenesis and sarcomere assembly. (c) 2006 Elsevier Inc. All rights reserved
Y1  - 2006
U6  - https://doi.org/10.1016/j.yexcr.2006.03.015
ER  - 
TY  - JOUR
A1  - Nagel, Birgit
A1  - Warsinke, Axel
T1  - Towards separation-free electrochemical affinity sensors by using antibodies, aptamers and molecularly imprinted polymers : a review
Y1  - 2006
U6  - https://doi.org/10.1080/00032710600853903
ER  - 
TY  - JOUR
A1  - Huber, Veronika
A1  - Gaedke, Ursula
T1  - The role of predation for seasonal variability patterns among phytoplankton and ciliates
N2  - Investigating the mechanisms which underlie the biomass fluctuations of populations and communities is important to better understand the processes which buffer community biomass in a variable environment. Based on long- term data of plankton biomass in Lake Constance (Bodensee), this study aims at explaining the different degree of synchrony among populations observed within two freshwater plankton groups, phytoplankton and ciliates. Established measures of temporal variability such as the variance ratio and cross-correlation coefficients were combined with first- order autoregressive models that allow estimating species interactions from time-series data. We found that predation was an important driver of the observed seasonal variability patterns in phytoplankton and ciliates, and that competitive interactions only played a subordinate role. In Lake Constance copepods and cladocerans, two major invertebrate predator groups, focus their grazing pressure at different times of the season. Model results suggested that compensatory dynamics detected in phytoplankton originate from the differential vulnerability of species to either one of these two predator groups. For ciliates model results advocated that synchrony among species occurs because ciliates tend to be vulnerable to both predator groups. Our findings underline the necessity of extending studies of community variability to multiple trophic levels because accounting for predator-prey interactions may often be more important than accounting for competitive interactions at one trophic level
Y1  - 2006
UR  - http://www3.interscience.wiley.com/cgi-bin/issn?DESCRIPTOR=PRINTISSN&VALUE=0030-1299
U6  - https://doi.org/10.1111/j.2006.0030-1299.14753.x
SN  - 0030-1299
ER  - 
TY  - THES
A1  - Kopka, Claudia
T1  - The nucleoside diphosphate kinases - a small gene family involved in the energyphosphotransfer of arabidopsis thaliana
Y1  - 2006
CY  - Potsdam
ER  - 
TY  - GEN
A1  - Lou, Ying
A1  - Ma, Hui
A1  - Lin, Wen-Hui
A1  - Chu, Zhao-Quing
A1  - Müller-Röber, Bernd
A1  - Xu, Zhi-Hong
A1  - Xue, Hong-Wei
T1  - The highly charged region of plant beta-type phosphatidylinositol 4-kinase is involved in membrane targeting and phospholipid binding
N2  - In Arabidopsis thaliana and Oryza sativa, two types of PI 4-kinase (PI4Ks) have been isolated and functionally characterized. The alpha-type PI4Ks (similar to 220 kDa) contain a PH domain, which is lacking in beta-type PI4Ks (similar to 120 kDa). beta-Type PI4Ks, exemplified by Arabidopsis AtPI4K beta and rice OsPI4K2, contain a highly charged repetitive segment designated PPC (Plant PI4K Charged) region, which is an unique domain only found in plant beta-type PI4Ks at present. The PPC region has a length of similar to 300 amino acids and harboring 11 (AtPI4K beta) and 14 (OsPI4K2) repeats, respectively, of a 20-aa motif. Studies employing a modified yeast-based "Sequence of Membrane- Targeting Detection'' system demonstrate that the PPC(OsPI4K2) region, as well as the former 8 and latter 6 repetitive motifs within the PPC region, are able to target fusion proteins to the plasma membrane. Further detection on the transiently expressed GFP fusion proteins in onion epidermal cells showed that the PPC(OsPI4K2) region alone, as well as the region containing repetitive motifs 1-8, was able to direct GFP to the plasma membrane, while the regions containing less repetitive motifs, i.e. 6, 4, 2 or single motif(s) led to predominantly intracellular localization. Agrobacterium-mediated transient expression of PPC-GFP fusion protein further confirms the membrane-targeting capacities of PPC region. In addition, the predominant plasma membrane localization of AtPI4Kb was mediated by the PPC region. Recombinant PPC peptide, expressed in E. coli, strongly binds phosphatidic acid, PI and PI4P, but not phosphatidylcholine, PI5P, or PI(4,5) P-2 in vitro, providing insights into potential mechanisms for regulating sub- cellular localization and lipid binding for the plant beta-type PI4Ks
Y1  - 2006
UR  - http://www.springerlink.com/content/100330
U6  - https://doi.org/10.1007/s11103-005-5548-x
SN  - 0167-4412
ER  - 
TY  - JOUR
A1  - Stalz, Holger
A1  - Roth, Udo
A1  - Schleuder, Detlev
A1  - Macht, Marcus
A1  - Haebel, Sophie
A1  - Strupat, Kerstin
A1  - Peter-Katalinic, Jasna
A1  - Hanisch, Franz-Georg
T1  - The Geodia cydonium galectin exhibits prototype and chimera-type characteristics and a unique sequence polymorphism within its carbohydrate recognition domain
N2  - The ancestral galectin from the sponge Geodia cydonium (GCG) is classified on a structural basis to the prototype subfamily, whereas its carbohydrate-binding specificity is related to that of the mammalian chimera-type galectin-3. This dual coordination reveals GCG as a potential precursor of the later evolved galectin subfamilies, which is reflected in the primary structure of the protein. This study provides evidence that GCG is the LECT1 gene product, while neither a previously described LECT2 gene nor a functional LECT2 gene product was found in the specimen under investigation. The electrophoretically separated protein isomers with apparent molecular masses of 13, 15, and 16 kDa correspond to variants of the LECT1 protein-exhibiting peptide sequence polymorphisms that concern critical positions of the carbohydrate recognition domain (13 kDa: Leu51, Asn55, His130, Gly137; 15 kDa: Ser51, Asn55, Asn130, Gly137; 16 kDa: Ser51, Tyr55, Asn130, Glu137). Four residues, highly conserved in the galectin family, are substituted. None of the residues claimed to be involved in interactions with GalNAc alpha 1-3 moieties at an extended binding subsite of galectin-3 was identified in the corresponding positions of GCG. Apparently, the substitutions do not confer distinct binding characteristics to the GCG variants as evidenced by binding studies with a recombinantly expressed 15-kDa isoform. The natural isoforms as well as the recombinant 15-kDa isoform oligomerize by the formation of non-covalent heteromeric or homomeric complexes. A phosphorylation of the galectin was confirmed neither by mass spectrometry nor by alkaline phosphatase treatment combined with isoelectric focusing
Y1  - 2006
UR  - http://glycob.oxfordjournals.org/content/16/5/402.full
U6  - https://doi.org/10.1093/glycob/cwj086
ER  - 
TY  - JOUR
A1  - Bleidorn, Christoph
A1  - Podsiadlowski, Lars
A1  - Bartolomaeus, Thomas
T1  - The complete mitochondrial genome of the orbiniid polychaete Orbinia latreillii (Annelida, Orbiniidae) : a novel gene order for Annelida and implications for annelid phylogeny
N2  - Relationships of annelid subtaxa are controversially discussed and additional markers are necessarily needed to get further insights into their evolution. Due to their high content of information, mitochondrial genomes have been proven very useful in phylogenetic analyses. Whereas many complete mitochondrial genomes of arthropods are available, lophotrochozoan taxa are only scarcely represented and this is especially true for annelids. Here we present the complete mitochondrial genome of the orbiniid polychaete Orbinia latreillii. The circular genome is 15,558 bp in size and contains the same 37 genes as found in most other metazoans. As in the case for all studied annelids all genes are transcribed from the same strand. Compared with the known data from other annelids at least five gene translocations must be hypothesized for O. latreillii. A comparison of the available data shows that gene translocations within Annelida seem to be less frequent than in molluscs, but more frequent as previously assumed. Phylogenetic analyses of mitochondrial DNA sequence data and amino acid data support an inclusion Of Sipuncula within Annelida and a closer relationship to orbiniids is recovered for this taxon.
Y1  - 2006
UR  - http://www.sciencedirect.com/science/journal/03781119
U6  - https://doi.org/10.1016/j.gene.2005.11.018
SN  - 0378-1119
ER  - 
TY  - JOUR
A1  - Wronski, Torsten
A1  - Apio, Ann
A1  - Plath, Martin
T1  - The communicatory significance of localised defecation sites in bushbuck (Tragelaphus scriptus)
N2  - Like several other mammals, bushbuck (Tragelaphus scriptus) deposit faeces in specific localised defecation sites (LDS). A previous study has ruled out a function of LDS in the context of parasite avoidance. In this study, we investigated the communicatory significance of LDS. In a free ranging population, we tested whether LDS serve to demarcate home ranges, and/or if LDS are used for communication in a non-territorial context. In both sexes, LDS increased significantly in number towards the periphery of individual home ranges. However, the distribution pattern of LDS, as revealed by a nearest-neighbour mapping technique (nearest distances between LDS), did not support the idea that LDS serve home range/territory-demarcation because LDS did not follow a pattern of minimal nearest-neighbour distances along the margins of home ranges. We found females to urinate more often in LDS than males. Notably, information transfer was most frequent between sending (urinating or defecating) females and receiving/responding males (urination or defecation at places where a female had previously signalled). Our results suggest that LDS mainly serve for inter- sexual communication in bushbuck
Y1  - 2006
UR  - http://www.springerlink.com/content/517tm6115561t421/
U6  - https://doi.org/10.1007/s00265-006-0174-4
ER  - 
TY  - JOUR
A1  - Lisso, Janina
A1  - Altmann, Thomas
A1  - Müssig, Carsten
T1  - The AtNFXL1 gene encodes a NF-X1 type zinc finger protein required for growth under salt stress
JF  - FEBS letters : the journal for rapid publication of short reports in molecular biosciences
N2  - The human NF-X1 protein and homologous proteins in eukaryotes represent a class of transcription factors which are characterised. by NF-X1 type zinc finger motifs. The Arabidopsis genome encodes two NF-X1 homologs, which we termed AtNFXL1 and AtNFXL2. Growth and survival was impaired in atnfxl1 knock-out mutants and AtNFXL1-antisense plants under salt stress in comparison to wild-type plants. In contrast, 35S: :AtNFXL1 plants showed higher survival rates. The AtNFXL2 protein potentially plays an antagonistic role. The Arabidopsis NF-X1 type zinc finger proteins likely are part of regulatory mechanisms, which protect major processes such as photosynthesis.
KW  - Arabidopsis thaliana
KW  - NF-X1
KW  - salt stress
Y1  - 2006
U6  - https://doi.org/10.1016/j.febslet.2006.07.079
SN  - 0014-5793
VL  - 580
IS  - 22
SP  - 4851
EP  - 4856
PB  - Elsevier
CY  - Amsterdam
ER  - 
TY  - JOUR
A1  - Bell, Elanor M.
A1  - Weithoff, Guntram
A1  - Gaedke, Ursula
T1  - Temporal dynamics and growth of Actinophrys sol (Sarcodina: Heliozoa), the top predator in an extremely acidic lake
N2  - 1. The in situ abundance, biomass and mean cell volume of Actinophrys sol (Sarcodina: Heliozoa), the top predator in an extremely acidic German mining lake (Lake 111; pH 2.65), were determined over three consecutive years (spring to autumn, 2001-03). 2. Actinophrys sol exhibited pronounced temporal and vertical patterns in abundance, biomass and mean cell volume. Increasing from very low spring densities, maxima in abundance and biomass were observed in late June/early July and September. The highest mean abundance recorded during the study was 7 x 10(3) Heliozoa L-1. Heliozoan abundance and biomass were higher in the epilimnion than in the hypolimnion. Actinophrys sol cells from this acidic lake were smaller than individuals of the same species found in other aquatic systems. 3. We determined the growth rate of A. sol using all potential prey items available in, and isolated and cultured from, Lake 111. Prey items included: single-celled and filamentous bacteria of unknown taxonomic affinity, the mixotrophic flagellates Chlamydomonas acidophila and Ochromonas sp., the ciliate Oxytricha sp. and the rotifers Elosa worallii and Cephalodella hoodi. Actinophrys sol fed over a wide-size spectrum from bacteria to metazoans. Positive growth was not supported by all naturally available prey. Actinophrys sol neither increased in cell number (k) nor biomass (k(b)) when starved, with low concentrations of single-celled bacteria or with the alga Ochromonas sp. Positive growth was achieved with single- celled bacteria (k = 0.22 +/- 0.02 d(-1); k(b) = -0.06 +/- 0.02 d(-1)) and filamentous bacteria (k = 0.52 +/- < 0.01 d(- 1); k(b) = 0.66 d(-1)) at concentrations greater than observed in situ, and the alga C. acidophila (up to k = 0.43 +/- 0.03 d(-1); k(b) = 0.44 +/- 0.04 d(-1)), the ciliate Oxytricha sp. (k = 0.34 +/- 0.01 d(-1)) and in mixed cultures containing rotifers and C. acidophila (k = 0.23 +/- 0.02-0.32 +/- 0.02 d(-1); maximum k(b) = 0.42 +/- 0.05 d(-1)). The individual- and biomass-based growth of A. sol was highest when filamentous bacteria were provided. 4. Existing quantitative carbon flux models for the Lake 111 food web can be updated in light of our results. Actinophrys sol are omnivorous predators supported by a mixed diet of filamentous bacteria and C. acidophila in the epilimnion. Heliozoa are important components in the planktonic food webs of 'extreme' environments
Y1  - 2006
UR  - http://www3.interscience.wiley.com/cgi-bin/issn?DESCRIPTOR=PRINTISSN&VALUE=0046-5070
U6  - https://doi.org/10.1111/j.1365-2427.2006.01561.x
SN  - 0046-5070
ER  - 
TY  - JOUR
A1  - Gerloff-Elias, Antje
A1  - Barua, Deepak
A1  - Mölich, Andreas
A1  - Spijkerman, Elly
T1  - Temperature- and pH-dependent accumulation of heat-shock proteins in the acidophilic green alga Chlamydomonas acidophila
N2  - Chlamydomonas acidophila, a unicellular green alga, is a dominant phytoplankton species in acidic water bodies, facing severe environmental conditions such as low pH and high heavy metal concentrations. We examined the pH-, and temperature-dependent accumulation of heat-shock proteins in this alga to determine whether heat-shock proteins play a role in adaptation to their environment. Our results show increased heat-shock proteins accumulation at suboptimal pHs, which were not connected with any change in intracellular pH. In comparison to the mesophilic Chlamydomonas reinhardtii, the acidophilic species exhibited significantly higher accumulations of heat-shock proteins under control conditions, indicating an environmental adaptation of increased basal levels of heat-shock proteins. The results suggest that heat- shock proteins might play a role in the adaptation of C. acidophila, and possibly other acidophilic algae, to their extreme environment
Y1  - 2006
UR  - http://www3.interscience.wiley.com/cgi-bin/issn?DESCRIPTOR=PRINTISSN&VALUE=0168-6496
U6  - https://doi.org/10.1111/j.1574-6941.2006.00078.x
SN  - 0168-6496
ER  - 
TY  - JOUR
A1  - Herzschuh, Ulrike
A1  - Kürschner, Harald
A1  - Mischke, Steffen
T1  - Temperature variability and vertical vegetation belt shifts during the last similar to 50,000 yr in the Qilian Mountains (NE margin of the Tibetan Plateau, China)
N2  - A 13.94-m-long sediment core, collected from a medium-sized lake in the Qilian Mountains (NE Tibetan Plateau, China), was analysed palynologically at 81 horizons. The interpretation of indicator taxa yielded various vertical shifts of the vegetation belts. These palaeovegetation results have been checked with lake surface pollen spectra from 8 takes representing different altitudinal vegetation belts. Our main findings are the following: A short period of the late Marine Isotope Stage 3 (around similar to 46,000 yr ago) was characterized by interglacial temperature conditions with a tree line above its present-day altitude. During the LGM, the vicinity of the lake was not covered by ice but by sparse alpine vegetation and alpine deserts, indicating that the climate was colder by similar to 4-7 degrees C than today Markedly higher temperatures were inferred from higher arboreal pollen frequencies between similar to 13,000 and similar to 7000 yr ago with a Holocene temperature optimum and a maximal Picea-Betula mixed-forest expansion between similar to 9000 and similar to 7000 yr ago, when temperatures exceeded the present-day conditions by at least 1-2 degrees C. Alpine steppes and meadows and sub-alpine shrub vegetation dominated around the lake since the middle Holocene, suggesting that vegetation and climate conditions were exceptionally stable in comparison to previous periods.
Y1  - 2006
UR  - http://www.sciencedirect.com/science/journal/00335894
U6  - https://doi.org/10.1016/j.yqres.2006.03.001
SN  - 0033-5894
ER  - 
TY  - JOUR
A1  - Köchy, Martin
T1  - Stochastic time series of daily precipitation for the interior of Israel
N2  - This contribution describes a generator of stochastic time series of daily precipitation for the interior of Israel from c. 90 to 900 mm mean annual precipitation (MAP) as a tool for studies of daily rain variability. The probability of rainfall on a given day of the year is described by a regular Gaussian peak curve function. The amount of rain is drawn randomly from an exponential distribution whose mean is the daily mean rain amount (averaged across years for each day of the year) described by a flattened Gaussian peak curve. Parameters for the curves have been calculated from monthly aggregated, long-term rain records from seven meteorological stations. Parameters for arbitrary points on the MAP gradient are calculated from a regression equation with MAP as the only independent variable. The simple structure of the generator allows it to produce time series with daily rain patterns that are projected under climate change scenarios and simultaneously control MAP. Increasing within-year variability of daily precipitation amounts also increases among-year variability of MAP as predicted by global circulation models. Thus, the time series incorporate important characteristics for climate change research and represent a flexible tool for simulations of daily vegetation or surface hydrology dynamics.
Y1  - 2006
UR  - 1960 = dx.doi.org/10.1560/IJES_55_2_103
ER  - 
TY  - GEN
A1  - Köchy, Martin
T1  - Stochastic time series of daily precipitation for the interior of Israel
N2  - This contribution describes a generator of stochastic time series of daily precipitation for the interior of Israel from c. 90 to 900 mm mean annual precipitation (MAP) as a tool for studies of daily rain variability. The probability of rainfall on a given day of the year is described by a regular Gaussian peak curve function. The amount of rain is drawn randomly from an exponential distribution whose mean is the daily mean rain amount (averaged across years for each day of the year) described by a flattened Gaussian peak curve. Parameters for the curves have been calculated from monthly aggregated, long-term rain records from seven meteorological stations. Parameters for arbitrary points on the MAP gradient are calculated from a regression equation with MAP as the only independent variable. The simple structure of the generator allows it to produce time series with daily rain patterns that are projected under climate change scenarios and simultaneously control MAP. Increasing within-year variability of daily precipitation amounts also increases among-year variability of MAP as predicted by global circulation models. Thus, the time series incorporate important characteristics for climate change research and represent a flexible tool for simulations of daily vegetation or surface hydrology dynamics.
T3  - Zweitveröffentlichungen der Universität Potsdam : Mathematisch-Naturwissenschaftliche Reihe - paper 029 
KW  - stochastische Zeitreihen
KW  - täglicher Niederschlag
KW  - Israel
KW  - Klimawandel
KW  - stochastic time series
KW  - daily precipitation
KW  - Israel
KW  - climate change
Y1  - 2006
U6  - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:kobv:517-opus-13155
ER  - 
TY  - THES
A1  - Mungur, Rajsree
T1  - Spatio-temporal analysis of florigenic signals in Arabidopsis thaliana, Sinapis alba and Brassica napus
T1  - Zeitabhängige Analyse von blühinduzierenden Signalen in Arabidopsis thaliana, Sinapis alba und Brassica napus
N2  - Daylength is one of several parameters controlling flowering time in many plant species. The day length is perceived in leaves, but how the floral signal is transduced to the shoot apex via the phloem to induce flowering remains to be elucidated. This study aimed at the identification of new candidates involved in the induction of flowering by employing three plant species, Arabidopsis thaliana, Sinapis alba and Brassica napus in combination with transcript profiling by Affymetrix chip hybridization, metabolite profiling by gas chromatography – mass spectrometry and targeted protein analysis using antibodies. All analyses were performed on tissue-specific samples and focused on phloem sap or phloem exudates. To find common transcript and metabolite candidates potentially associated with the floral transition, two independent induction systems in Arabidopsis were used: a photoextension system, whereby plants received fourteen additional hours of light, and a parallel dexamethasone-inducible system, which was centered on the induction of the known flowering gene CONSTANS (CO). Identification of signals preceding the CO cascade was possible using the light extension regime, while downstream events dependent on CO activation were compared in both systems. Altogether, a number of interesting transcript and metabolite candidates were identified in both systems with some degree of overlap. Sinapis alba was used to investigate the universality of the floral signals between species. Comparisons of metabolite data revealed a few common candidates that may prove interesting for further studies. In addition, a targeted approach was carried out to investigate the presence of the Flowering Locus T (FT) protein during different stages of flower development using an antibody. Interesting changes in the sizes of antigens from rape phloem were seen and appeared consistent in Arabidopsis and to a lesser extent in Sinapis. Overall, the broad surveying approaches for transcripts and metabolites used in this study revealed several new potential candidates involved in the induction and/or regulation of flowering. As far as the protein work, additional experiments will reveal the link between FT and floral induction as well as its role in maintaining the floral state using the abovementioned plant species.
N2  - Die Tageslänge ist in vielen Pflanzenarten einer der Parameter, welche die Blütenbildung kontrollieren. Die Tageslänge wird in Blättern gemessen, aber wie das blühinduzierende Signal über das Phloem in den Apex übertragen wird ist bisher nicht aufgeklärt. Die vorliegende Arbeit hatte das Ziel neue Kandidaten zu identifizieren, die an der Blühinduktion beteiligt sind. Dazu wurden die drei Pflanzenarten Arabidopsis thaliana, Sinapis alba und Brassica napus auf der Ebene von Transkripten durch Affymetrix Chip Hybridisierungen, Metaboliten durch Gaschromatographie-Massenspektrometrie und ausgesuchten Proteinen durch Antikörper analysiert. Alle Untersuchungen wurden an gewebespezifischen Proben vorgenommen und waren auf Phloemsaft bzw. Phloemexsudate fokussiert. Um gemeinsame Transkript- und Metabolitkandidaten zu ermitteln, welche mit der Blühinduktion in Zusammenhang stehen, wurden zwei unabhängige Induktionssysteme in Arabidopsis verwendet: Ein Photoextensions-System, in dem die Pflanzen vierzehn zusätzlichen Stunden Licht ausgesetzt wurden und ein paralleles Dexamethason-induzierbares System, das die gezielte Aktivierung des bekannten blühinduzierenden Gens CONSTANS (CO) ermöglicht. Die Identifikation von CO-vorgelagerten Signalen war in dem Photoextensions-System möglich, während der CO-Aktivierung nachgelagerte Ereignisse in beiden Systemen verglichen werden konnten. Zusammengenommen konnten mit beiden Systemen eine Reihe von interessanten Transkript- und Metabolitkandidaten ermittelt werden, welche auch teilweise überlappten. Anschließend wurde Sinapis alba verwendet, um die Universalität der blühinduzierenden Signale in verschiedenen Pflanzenarten zu untersuchen. Vergleiche der Metabolitendaten ergaben ein paar gemeinsame Kandidaten, welche für weitergehende Untersuchungen interessant sein könnten. Zusätzlich wurden mittels Antikörpern gezielte Untersuchungen bezüglich der Präsenz des Flowering Locus T (FT) Proteins während verschiedener Stadien der Blütenentwicklung durchgeführt. Diese Untersuchungen zeigten interessante Änderungen der Größe des Antigens in Raps Phloemsaft, welche auch in Arabidopsis und in geringerem Maße in Sinapis sichtbar waren. Zusammengefasst resultierten die umfassenden Transkript- und Metabolitenmessungen, die in dieser Arbeit verwendet wurden, in einer Reihe von neuen möglichen Kandidaten, welche an der Induktion und/oder Regulation der Blütenbildung beteiligt sein könnten. Bezüglich des Proteins FT sind zusätzliche Experimente notwendig, um seine Rolle bei der Blühinduktion bzw. bei der Aufrechterhaltung des blühenden Zustandes aufzudecken.
KW  - Florigen
KW  - Florigen
Y1  - 2006
U6  - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:kobv:517-opus-9861
ER  - 
TY  - GEN
A1  - Neye, Gundula
A1  - Wallschläger, Hans-Dieter
A1  - Tiedemann, Ralph
T1  - Song dialect boundaries in the Yellowhammer: Do they restrict gene flow?
T2  - Journal of ornithology
Y1  - 2006
SN  - 0021-8375
VL  - 147
IS  - Supplement 1
SP  - 219
EP  - 219
PB  - Blackwell
CY  - New York
ER  - 
TY  - JOUR
A1  - Heinken, Thilo
A1  - Schmidt, Marcus
A1  - von Oheimb, Goddert
A1  - Kriebitzsch, Wolf-Ulrich
A1  - Ellenberg, Hermann
T1  - Soil seed banks near rubbing trees indicate dispersal of plant species into forests by wild boar
N2  - Current knowledge about processes that generate long-distance dispersal of plants is still limited despite its importance for persistence of populations and colonization of new potential habitats. Today wild Large mammals are presumed to be important vectors for long-distance transport of diaspores within and between European temperate forest patches, and in particular wild boars recently came into focus. Here we use a specific habit of wild boar, i.e. wallowing in mud and subsequent rubbing against trees, to evaluate epizoochorous dispersal of vascular plant diaspores. We present soil seed bank data from 27 rubbing trees versus 27 control trees from seven forest areas in Germany. The mean number of viable seeds and the plant species number were higher in soil samples near rubbing trees compared with control trees. Ten of the 20 most frequent species were more frequent, and many species exclusively appeared in the soil samples near rubbing trees. The large number of plant species and seeds - more than 1000 per tree - in the soils near rubbing trees is difficult to explain unless the majority were dispersed by wild boar. Hooked and bristly diaspores, i.e. those adapted to epizoochory, were more frequent; however, many species with unspecialized diaspores occurred exclusively near rubbing trees. As opposed to plant species closely tied to forests species which occur both in forest and open vegetation and non-forest species were more frequent near rubbing trees compared with controls. These findings are consistent with previous studies on diaspore loads in the coats and hooves of shot wild boars. However, our method allows to identify the transport of diaspores from the open landscape into forest stands, where they might especially emerge after disturbance, and a clustered distribution of epizoochorically dispersed seeds. Moreover, accumulation of seeds of wetness indicators near rubbing trees demonstrates directed dispersal of plant species inhabiting wet places among remote wallows.
Y1  - 2006
UR  - http://www.sciencedirect.com/science/journal/14391791
U6  - https://doi.org/10.1016/j.baae.2005.04.006
SN  - 1439-1791
ER  -