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There is a fundamental gap in our understanding of how horizontal gene transfer contributes to the enormous range of genetic variations that are observed among bacteria. Our model organism is Vibrio cholerae, the causative agent of cholera. V. cholerae enters a natural competence state for the uptake of DNA in response to environmental signals. Our objective is to better understand the regulatory circuits that drive competence in this organism and the mechanistic aspects of the DNA transfer and uptake process.

Grossflachige Klassifikation von Gebuschwald mit Fernerkundungsdaten Informationen uber die Ausdehnung und die Entwicklung von Gebuschwaldern sind fur verschiedene forstliche und okologische Fragestellungen von Bedeutung, jedoch sind aktuelle und flachendeckende Datensatze kaum verfugbar. Im Rahmen dieser Arbeit wurde die Kartierung des Gebuschwaldes mit Dominanz von Alpenerle, Legfohre und Hasel fur den Kanton Graubunden auf Basis von landesweit verfugbaren Fernerkundungsdaten untersucht. Es wurden die Satellitendaten von Sentinel-1 und Sentinel-2 sowie ein Vegetationshohenmodell und ein Gelandemodell verwendet. Fur die uberwachte Klassifikation mit Random Forest, einem auf Entscheidungsbaumen basierenden Verfahren des maschinellen Lernens, wurden vom Kanton bereitgestellte und durch Luftbildinterpretation erganzte Trainingsflachen verwendet. Die unabhangige Validierung der Ergebnisse wurde mit Daten des Landesforstinventars (LFI) durchgefuhrt. Alpenerlen- und Legfohrenwalder liessen sich mit einer hohen Genauigkeit von 92.1% bzw. 86.7% klassifizieren, fur Haselwalder betrug die interne Modellgute hingegen nur 66.7%. Die resultierende Flachenausdehnung des Gebuschwaldes war vergleichbar mit den Angaben des LFI. Beim direkten Vergleich mit den LFI-Luftbildinterpretationspunkten wurden grossere Abweichungen festgestellt. Der Hauptgrund dafur ist der unterschiedliche raumliche Detaillierungsgrad. LFI-Flachen mit einem hohen Strauchanteil wurden jedoch zuverlassig als Gebuschwald klassifiziert. Die hier vorgestellte Methode unterstreicht das Potenzial von schweizweit verfugbaren Fernerkundungsdaten fur eine weitgehend objektive, kosteneffiziente und grossflachige Kartierung von Gebuschwaldern in einer fur die Praxis genugenden Genauigkeit. Large-scale classification of shrub forest with remote sensing data: Information on shrub forest distribution and development is important for a range of forestry- and ecologically-related questions, but current and area-wide datasets have been characterized by limited availability. In this study, the mapping of shrub forests dominated by green alder, mountain pine and hazel for the canton of Grison was investigated, based on available nationwide remote sensing data. Satellite data from Sentinel-1 and Sentinel-2, as well as a vegetation height and an elevation model were used. Training areas provided by the canton and supplemented by aerial imagery interpretation were used for a supervised classification with Random Forest, a decision tree-based machine learning algorithm. Independent validation of the results was carried out with data from the National Forest Inventory (NFI). Green alder and mountain pine forests were classified with high accuracy of 92.1% respectively 86.7%, whereas for hazel shrub forests, the internal model accuracy was only 66.7%. The resulting area expansion of the shrub forest was comparable with findings based on the NFI. A direct comparison with the NFI aerial imagery interpretation points revealed major discrepancies. The main reason for this is the different degree of spatial detail. However, NFI areas with a high percentage of shrubs were reliably classified as shrub forest. The method presented here underscores the potential of remote sensing data available throughout Switzerland for an essentially objective, costefficient and large-scale mapping of shrub forests with an accuracy applicable in practice.

The purinergic P2X7 receptor (P2X7R) has attracted considerable interest as a potential target for various central nervous system (CNS) pathologies including affective and neurodegenerative disorders. To date, the distribution and cellular localization of the P2X7R in the brain are not fully resolved and a matter of debate mainly due to the limitations of existing tools. However, this knowledge should be a prerequisite for understanding the contribution of the P2X7R to brain disease. Here, we generated a genetic mouse model by humanizing the P2X7R in the mouse as mammalian model organism. We demonstrated its functionality and revealed species-specific characteristics of the humanized receptor, compared to the murine ortholog, regarding its receptivity to activation and modulation by 2′,3′-O-(benzoyl-4-benzoyl)-adenosine 5′-triphosphate (BzATP) and trifluoperazine (TFP). This humanized P2rx7 allele is accessible to spatially and temporally controlled Cre recombinase-mediated inactivation. In contrast to previously generated knockout (KO) mice, none of the described P2rx7 splice variants evade this null allele. By selective disruption and assessment of human P2RX7 expression in different brain regions and cell types, we were able to demonstrate that the P2X7R is specifically expressed in glutamatergic pyramidal neurons of the hippocampus. Also, P2X7R is expressed in major non-neuronal lineages throughout the brain, i.e., astrocytes, oligodendrocytes, and microglia. In conclusion, this humanized mouse model provides the means for detailed assessment of human P2X7R function in vivo including evaluation of agonists or antagonists. In addition, this conditional allele will enable future loss-of-function studies in conjunction with mouse models for CNS disorders. Fil: Metzger, Michael W.. Max Planck Institut Fur Psychiatrie; Alemania Fil: Walser, Sandra M.. Max Planck Institut Fur Psychiatrie; Alemania Fil: Aprile García, Fernando. Consejo Nacional de Investigaciones Científicas y Técnicas. Oficina de Coordinación Administrativa Parque Centenario. Instituto de Investigación en Biomedicina de Buenos Aires - Instituto Partner de la Sociedad Max Planck; Argentina Fil: Dedic, Nina. Max Planck Institut Fur Psychiatrie; Alemania Fil: Chen, Alon. Helmholtz Center Munich German Research Center For Environmental Health; Alemania. Max Planck Institut Fur Psychiatrie; Alemania Fil: Holsboer, Florian. Max Planck Institut Fur Psychiatrie; Alemania Fil: Arzt, Eduardo Simon. Consejo Nacional de Investigaciones Científicas y Técnicas. Oficina de Coordinación Administrativa Parque Centenario. Instituto de Investigación en Biomedicina de Buenos Aires - Instituto Partner de la Sociedad Max Planck; Argentina Fil: Wurst, Wolfgang. Ludwig Maximilians Universitat; Alemania. Weizmann Institute Of Science Israel; Israel. Universitat Technical Zu Munich; Alemania Fil: Deussing, Jan M.. Max Planck Institut Fur Psychiatrie; Alemania

Analysis of observations and model projections provides large-scale emergent constraints on the extent of CO2 fertilization, with estimated increases in gross primary productivity for both high-latitude and extratropical ecosystems under elevated atmospheric CO2 concentrations. Climate–carbon cycle models generally assume that elevated atmospheric CO2 concentrations will enhance terrestrial plant productivity. But the magnitude of this so-called CO2 fertilization effect remains uncertain—with implications for future climate change projections. This study provides large-scale constraints on the extent of CO2 fertilization with an estimated increase in gross primary productivity of 37 ± 9 per cent for high-latitude ecosystems and 32 ± 9 per cent for extratropical ecosystems for a doubling of atmospheric CO2 concentrations. Uncertainties in the response of vegetation to rising atmospheric CO2 concentrations1,2 contribute to the large spread in projections of future climate change3,4. Climate–carbon cycle models generally agree that elevated atmospheric CO2 concentrations will enhance terrestrial gross primary productivity (GPP). However, the magnitude of this CO2 fertilization effect varies from a 20 per cent to a 60 per cent increase in GPP for a doubling of atmospheric CO2 concentrations in model studies5,6,7. Here we demonstrate emergent constraints8,9,10,11 on large-scale CO2 fertilization using observed changes in the amplitude of the atmospheric CO2 seasonal cycle that are thought to be the result of increasing terrestrial GPP12,13,14. Our comparison of atmospheric CO2 measurements from Point Barrow in Alaska and Cape Kumukahi in Hawaii with historical simulations of the latest climate–carbon cycle models demonstrates that the increase in the amplitude of the CO2 seasonal cycle at both measurement sites is consistent with increasing annual mean GPP, driven in part by climate warming, but with differences in CO2 fertilization controlling the spread among the model trends. As a result, the relationship between the amplitude of the CO2 seasonal cycle and the magnitude of CO2 fertilization of GPP is almost linear across the entire ensemble of models. When combined with the observed trends in the seasonal CO2 amplitude, these relationships lead to consistent emergent constraints on the CO2 fertilization of GPP. Overall, we estimate a GPP increase of 37 ± 9 per cent for high-latitude ecosystems and 32 ± 9 per cent for extratropical ecosystems under a doubling of atmospheric CO2 concentrations on the basis of the Point Barrow and Cape Kumukahi records, respectively.

Oasis Park Fuerteventura is a big amusement park with a zoological and a botanical garden.The latter is described here. In this garden, plants of the Canary Islands are cultivated, including rare endemic species. Plants of different ecosystems like succulent scrub and thermophilous forest are displayed.The garden also hosts many other plants, including tropical tree and shrub species and many different palms, as well as a large succulent plant assemblage with cacti, succulent plants from Madagascar, aloes, yuccas and agaves., Der Palmengarten, Bd. 78 Nr. 1 (2014)

New sequencing technologies are currently revolutionizing the field of genomic research. They enable researchers to investigate genomes and transcriptomes at previously unachieved depth and level of detail. The combination of functional genomics with next generation sequencing will facilitate new experimental strategies for addressing complex biological phenomena and will give us fundamental insights in the underlying geno- me organization and biology of model organism.

Sulfolobus solfataricus hat sich als archaealer Modellorganismus etabliert und ist aufgrund seiner besonderen Stoffwechseleigenschaften von groser Bedeutung fur die Untersuchung des archaealen Zuckerstoffwechsels und zukunftige biotechnologische Anwendungen.

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