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991.
The ubiquitously expressed transmembrane enzyme Na,K-ATPase (NKA) is vital in maintaining functionality of cells. The association of α- and β-subunits is believed to be essential for forming a functional enzyme. In the large milkweed bug Oncopeltus fasciatus four α1-paralogs and four β-subunits exist that can associate into NKA complexes. This diversity raises the question of possible tissue-specific distribution and function. While the α1-subunits are known to modulate cardenolide-resistance and ion-transport efficiency, the functional importance of the β-subunits needed further investigation. We here characterize all four different β-subunits at the cellular, tissue, and whole organismal scales. A knockdown of different β-subunits heavily interferes with molting success resulting in strongly hampered phenotypes. The failure of ecdysis might be related to disrupted septate junction (SJ) formation, also reflected in β2-suppression-induced alteration in tracheal morphology. Our data further suggest the existence of isolated β-subunits forming homomeric or β-heteromeric complexes. This possible standalone and structure-specific distribution of the β-subunits predicts further, yet unknown pump-independent functions. The different effects caused by β knockdowns highlight the importance of the various β-subunits to fulfill tissue-specific requirements. 相似文献
992.
Lishani Wijewardene Julia Anna Schwenker Meike Friedrichsen Ailina Jensen Franziska Löbel Tabea Austen Uta Ulrich Nicola Fohrer Corinna Bang Silvio Waschina Christina Susanne Hölzel 《Environmental microbiology》2023,25(12):2972-2987
Herbicides are important, ubiquitous environmental contaminants, but little is known about their interaction with bacterial aquatic communities. Here, we sampled a protected natural freshwater habitat and characterised its microbiome in interaction with herbicides. We evolved the freshwater microbiomes in a microcosm assay of exposure (28 days) to flufenacet and metazachlor at environmental concentrations of 0.5, 5 and 50 μg L−1. Inhibitory effects of herbicides were exemplarily assessed in cultured bacteria from the same pond (Pseudomonas alcaligenes, Paenibacillus amylolyticus and Microbacterium hominis). Findings were compared to long-term concentrations as provided by local authorities. Here, environmental concentrations reached up to 11 μg L−1 (flufenacet) and 76 μg L−1 (metazachlor). Bacteria were inhibited at minimum inhibitory concentrations far above these values; however, concentrations of 50 μg L−1 of flufenacet resulted in measurable growth impairment. While most herbicide-exposed microcosm assays did not differ from controls, Acidobacteria were selected at high environmental concentrations of herbicides. Alpha-diversity (e.g., taxonomic richness on phylum level) was reduced when aquatic microbiomes were exposed to 50 μg metazachlor or flufenacet. One environmental strain of P. alcaligenes showed resistance to high concentrations of flufenacet (50 g L−1). In total, this study reveals that ecologic imbalance due to herbicide use significantly impacts aquatic microbiomes. 相似文献
993.
Faidon Magkos Inge Tetens Susanne Gjedsted Bügel Claus Felby Simon Rnnow Schacht James O. Hill Eric Ravussin Arne Astrup 《Obesity (Silver Spring, Md.)》2020,28(1):73-79
Emissions of greenhouse gases (GHG) are linked to global warming and adverse climate changes. Meeting the needs of the increasing number of people on the planet presents a challenge for reducing total GHG burden. A further challenge may be the size of the average person on the planet and the increasing number of people with excess body weight. We used data on GHG emissions from various sources and estimated that obesity is associated with ~20% greater GHG emissions compared with the normal‐weight state. On a global scale, obesity contributes to an extra GHG emissions of ~49 megatons per year of CO2 equivalent (CO2eq) from oxidative metabolism due to greater metabolic demands, ~361 megatons per year of CO2eq from food production processes due to increased food intake, and ~290 megatons per year of CO2eq from automobile and air transportation due to greater body weight. Therefore, the total impact of obesity may be extra emissions of ~700 megatons per year of CO2eq, which is about 1.6% of worldwide GHG emissions. Inasmuch as obesity is an important contributor to global GHG burden, strategies to reduce its prevalence should prioritize efforts to reduce GHG emissions. Accordingly, reducing obesity may have considerable benefits for both public health and the environment. 相似文献
994.
Rafael O. Wüest Niklaus E. Zimmermann Damaris Zurell Jake M. Alexander Susanne A. Fritz Christian Hof Holger Kreft Signe Normand Juliano Sarmento Cabral Eniko Szekely Wilfried Thuiller Martin Wikelski Dirk Nikolaus Karger 《Journal of Biogeography》2020,47(1):1-12
Recent years have seen an exponential increase in the amount of data available in all sciences and application domains. Macroecology is part of this “Big Data” trend, with a strong rise in the volume of data that we are using for our research. Here, we summarize the most recent developments in macroecology in the age of Big Data that were presented at the 2018 annual meeting of the Specialist Group Macroecology of the Ecological Society of Germany, Austria and Switzerland (GfÖ). Supported by computational advances, macroecology has been a rapidly developing field over recent years. Our meeting highlighted important avenues for further progress in terms of standardized data collection, data integration, method development and process integration. In particular, we focus on (a) important data gaps and new initiatives to close them, for example through space- and airborne sensors, (b) how various data sources and types can be integrated, (c) how uncertainty can be assessed in data-driven analyses and (d) how Big Data and machine learning approaches have opened new ways of investigating processes rather than simply describing patterns. We discuss how Big Data opens up new opportunities, but also poses new challenges to macroecological research. In the future, it will be essential to carefully assess data quality, the reproducibility of data compilation and analytical methods, and the communication of uncertainties. Major progress in the field will depend on the definition of data standards and workflows for macroecology, such that scientific quality and integrity are guaranteed, and collaboration in research projects is made easier. 相似文献
995.
Plant and Soil - The paper by Korboulewsky and co-authors in this issue of Plant and Soil address some of the central questions of critical zone ecohydrology: how do plants interact with rocks that... 相似文献
996.
Elena Marinova Sandy P. Harrison Fran Bragg Simon Connor Veronique de Laet Suzanne A.G. Leroy Petra Mudie Juliana Atanassova Elissaveta Bozilova Hülya Caner Carlos Cordova Morteza Djamali Mariana Filipova‐Marinova Natalia Gerasimenko Susanne Jahns Katerina Kouli Ulrich Kotthoff Eliso Kvavadze Maria Lazarova Elena Novenko Elias Ramezani Astrid Röpke Lyudmila Shumilovskikh Ioan Tanţǎu Spassimir Tonkov 《Journal of Biogeography》2018,45(2):484-499
997.
998.
999.
Rolf G. Beutel Dominique Zimmermann Marcus Krauß Susanne Randolf Benjamin Wipfler 《Organisms Diversity & Evolution》2010,10(4):311-329
External and internal head structures of Osmylus fulvicephalus were examined and described in detail. Exo- and endoskeleton, musculature, elements of the central nervous system and tracheae
are compared to conditions found in other groups of Neuropterida and other endopterygote lineages. Thirty-six adult cephalic
characters were compiled, combined in a datamatrix with 64 characters of the larval head, and analysed cladistically. Mainly
because many data on adults remain missing, most branches in the cladogram are mostly or exclusively supported by larval features.
The shortening of the mesal mandibular wall and the resulting anterior shift of the adductor tendon possibly constitute an
adult groundplan apomorphy of Neuropterida. Raphidioptera and Megaloptera share distinct prognathism and the presence of a
sclerotised gula. However, the orthognathous head and the absence of a gula resulted as autapomorphies of Neuroptera in our
analyses. Further potential autapomorphies are the asymmetry of the mandibles as well as the respective presence of dorsolateral
furrows on the head capsule, of a shovel-like extension on the ventral mandibular cutting edge, and of a row of stiff hairs
on the mandible’s ventral surface. The systematic affinities of Osmylidae remain ambiguous. Osmylus is mainly characterised by plesiomorphic features of the adult head such as a complete endoskeleton, long filiform antennae,
largely unmodified orthopteroid mouthparts, and particularly the nearly complete set of muscles. The placement with a clade
also comprising Hemerobiidae and Chrysopidae is poorly supported. The presence of a dense vestiture of long microtrichia on
the distal galeomere resulted as a synapomorphy of the three families. An apparent plesiomorphy preserved in Osmylus but absent in all other groups of Neuroptera is the presence of well developed ocelli. The present study underlines the severe
shortage of detailed morphological data on the adults. Intensive study of adult structures is required for a solid reconstruction
of the phylogeny of Neuropterida, especially of the hemerobiform lineage of Neuroptera. 相似文献
1000.
Aline Jatho Svenja Hartmann Naim Kittana Felicitas Mügge Christina M. Wuertz Malte Tiburcy Wolfram-Hubertus Zimmermann D?rthe M. Katschinski Susanne Lutz 《PloS one》2015,10(10)
IntroductionRhoA has been shown to be beneficial in cardiac disease models when overexpressed in cardiomyocytes, whereas its role in cardiac fibroblasts (CF) is still poorly understood. During cardiac remodeling CF undergo a transition towards a myofibroblast phenotype thereby showing an increased proliferation and migration rate. Both processes involve the remodeling of the cytoskeleton. Since RhoA is known to be a major regulator of the cytoskeleton, we analyzed its role in CF and its effect on myofibroblast characteristics in 2 D and 3D models.ResultsDownregulation of RhoA was shown to strongly affect the actin cytoskeleton. It decreased the myofibroblast marker α-sm-actin, but increased certain fibrosis-associated factors like TGF-β and collagens. Also, the detailed analysis of CTGF expression demonstrated that the outcome of RhoA signaling strongly depends on the involved stimulus. Furthermore, we show that proliferation of myofibroblasts rely on RhoA and tubulin acetylation. In assays accessing three different types of migration, we demonstrate that RhoA/ROCK/Dia1 are important for 2D migration and the repression of RhoA and Dia1 signaling accelerates 3D migration. Finally, we show that a downregulation of RhoA in CF impacts the viscoelastic and contractile properties of engineered tissues.ConclusionRhoA positively and negatively influences myofibroblast characteristics by differential signaling cascades and depending on environmental conditions. These include gene expression, migration and proliferation. Reduction of RhoA leads to an increased viscoelasticity and a decrease in contractile force in engineered cardiac tissue. 相似文献