Neue Wege zur Schaffung struktur- und artenreicher Waldränder im Kreis Höxter

Die Bundesrepublik hat sich 1992 wie viele andere Staaten zum Erhalt der biologischen Vielfalt verpflichtet (Biodiversitätskonvention). Zur Erreichung dieses Zieles fördert das Bundesministerium für Ernährung, Landwirtschaft und Verbraucherschutz (BMELV) u. a. Vorhaben zur Erhaltung und innovativen nachhaltigen Nutzung der biologischen Vielfalt. Grundlage der Förderung ist eine Richtlinie von 2005. Träger entsprechender Projekte ist die Bundesanstalt für Landwirtschaft und Ernährung (BLE). Bereits 2006 hatte die Landschaftsstation zusammen mit dem damaligen Forstamt Bad Driburg einen Projektantrag eingereicht, bei dem es um die Wiederbelebung der Nieder- und Mittelwaldnutzung im Bereich der im Kreis Höxter ehemals zahlreichen Nieder- und Mittelwälder ging (vgl. GRAWE & BÖLKE 2005). Da zunächst nur recht kleine Waldareale in das Vorhaben einbezogen werden sollten, wurde der Antrag abgelehnt. Anfang 2007 fragte die BLE bei der Landschaftsstation an, ob es nicht möglich sei, die Gebietskulisse zu erweitern, da der Projektantrag grundsätzlich als förderfähig angesehen werde. Aufgrund dieser Anfrage erarbeiteten das heutige Regionalforstamt Hochstift und die Landschaftsstation einen neuen Projektantrag mit dem Titel "Mittelwaldähnliche Waldrandgestaltung und -nutzung zur Förderung der Nutzholzarten Stiel-Eiche, Trauben-Eiche und Hainbuche sowie seltener Edellaub- und Nadelgehölze wie Elsbeere, Wacholder oder Eibe", der dann im Herbst des gleichen Jahres durch die BLE bewilligt wurde, so dass bereits im Oktober 2007 mit der Umsetzung des Vorhabens begonnen werden konnte. Vorrangiges naturschutzfachliches Ziel des Vorhabens ist die Förderung der in ihren Beständen im Rückgang befindlichen lichtliebenden Nutzholzarten Trauben-Eiche (Quercus petraea), Stiel-Eiche (Quercus robur), Hainbuche (Carpinus betulus), Feld-Ahorn (Acer campestre), Winter-Linde (Tilia cordata), Elsbeere (Sorbus torminalis), Wacholder (Juniperus communis) und Eibe (Taxus baccata). Die Förderung dieser Baumarten soll im Rahmen einer mittelwaldähnlichen Nutzung von Waldrändern geschehen. Eine ökonomische Inwertsetzung erfolgt im Rahmen einer einmaligen Erstinstandsetzung sowie des nachfolgenden regelmäßigen Einschlages des nachwachsenden Holzes (alle 15-30 Jahre). Das dann eingeschlagene Holz wird zur Energiegewinnung (Hackschnitzel) genutzt

The Role of Cdc42 and Gic1 in the Regulation of Septin Filament Formation and Dissociation

Septins are guanine nucleotide-binding proteins that polymerize into filamentous and higher-order structures. Cdc42 and its effector Gic1 are involved in septin recruitment, ring formation and dissociation. The regulatory mechanisms behind these processes are not well understood. Here, we have used electron microscopy and cryo electron tomography to elucidate the structural basis of the Gic1-septin and Gic1-Cdc42-septin interaction. We show that Gic1 acts as a scaffolding protein for septin filaments forming long and flexible filament cables. Cdc42 in its GTP-form binds to Gic1, which ultimately leads to the dissociation of Gic1 from the filament cables. Surprisingly, Cdc42-GDP is not inactive, but in the absence of Gic1 directly interacts with septin filaments resulting in their disassembly. We suggest that this unanticipated dual function of Cdc42 is crucial for the cell cycle. Based on our results we propose a novel regulatory mechanism for septin filament formation and dissociation. DOI: http://dx.doi.org/10.7554/eLife.01085.00

Topography of Lipid Droplet-Associated Proteins: Insights from Freeze-Fracture Replica Immunogold Labeling

Lipid droplets are not merely storage depots for superfluous intracellular lipids in times of hyperlipidemic stress, but metabolically active organelles involved in cellular homeostasis. Our concepts on the metabolic functions of lipid droplets have come from studies on lipid droplet-associated proteins. This realization has made the study of proteins, such as PAT family proteins, caveolins, and several others that are targeted to lipid droplets, an intriguing and rapidly developing area of intensive inquiry. Our existing understanding of the structure, protein organization, and biogenesis of the lipid droplet has relied heavily on microscopical techniques that lack resolution and the ability to preserve native cellular and protein composition. Freeze-fracture replica immunogold labeling overcomes these disadvantages and can be used to define at high resolution the precise location of lipid droplet-associated proteins. In this paper illustrative examples of how freeze-fracture immunocytochemistry has contributed to our understanding of the spatial organization in the membrane plane and function of PAT family proteins and caveolin-1 are presented. By revisiting the lipid droplet with freeze-fracture immunocytochemistry, new perspectives have emerged which challenge prevailing concepts of lipid droplet biology and may hopefully provide a timely impulse for many ongoing studies

Mesenchymal stromal cells inhibit NLRP3 inflammasome activation in a model of Coxsackievirus B3-induced inflammatory cardiomyopathy

Inflammation in myocarditis induces cardiac injury and triggers disease progression to heart failure. NLRP3 inflammasome activation is a newly identified amplifying step in the pathogenesis of myocarditis. We previously have demonstrated that mesenchymal stromal cells (MSC) are cardioprotective in Coxsackievirus B3 (CVB3)-induced myocarditis. In this study, MSC markedly inhibited left ventricular (LV) NOD2, NLRP3, ASC, caspase-1, IL-1β, and IL-18 mRNA expression in CVB3-infected mice. ASC protein expression, essential for NLRP3 inflammasome assembly, increased upon CVB3 infection and was abrogated in MSC-treated mice. Concomitantly, CVB3 infection in vitro induced NOD2 expression, NLRP3 inflammasome activation and IL-1β secretion in HL-1 cells, which was abolished after MSC supplementation. The inhibitory effect of MSC on NLRP3 inflammasome activity in HL-1 cells was partly mediated via secretion of the anti-oxidative protein stanniocalcin-1. Furthermore, MSC application in CVB3-infected mice reduced the percentage of NOD2-, ASC-, p10- and/or IL-1β- positive splenic macrophages, natural killer cells, and dendritic cells. The suppressive effect of MSC on inflammasome activation was associated with normalized expression of prominent regulators of myocardial contractility and fibrosis to levels comparable to control mice. In conclusion, MSC treatment in myocarditis could be a promising strategy limiting the adverse consequences of cardiac and systemic NLRP3 inflammasome activation

The Discovery of LOX-1, its Ligands and Clinical Significance

LOX-1 is an endothelial receptor for oxidized low-density lipoprotein (oxLDL), a key molecule in the pathogenesis of atherosclerosis.The basal expression of LOX-1 is low but highly induced under the influence of proinflammatory and prooxidative stimuli in vascular endothelial cells, smooth muscle cells, macrophages, platelets and cardiomyocytes. Multiple lines of in vitro and in vivo studies have provided compelling evidence that LOX-1 promotes endothelial dysfunction and atherogenesis induced by oxLDL. The roles of LOX-1 in the development of atherosclerosis, however, are not simple as it had been considered. Evidence has been accumulating that LOX-1 recognizes not only oxLDL but other atherogenic lipoproteins, platelets, leukocytes and CRP. As results, LOX-1 not only mediates endothelial dysfunction but contributes to atherosclerotic plaque formation, thrombogenesis, leukocyte infiltration and myocardial infarction, which determine mortality and morbidity from atherosclerosis. Moreover, our recent epidemiological study has highlighted the involvement of LOX-1 in human cardiovascular diseases. Further understandings of LOX-1 and its ligands as well as its versatile functions will direct us to ways to find novel diagnostic and therapeutic approaches to cardiovascular disease

Structure of Mega-Hemocyanin Reveals Protein Origami in Snails

SummaryMega-hemocyanin is a 13.5 MDa oxygen transporter found in the hemolymph of some snails. Similar to typical gastropod hemocyanins, it is composed of 400 kDa building blocks but has additional 550 kDa subunits. Together, they form a large, completely filled cylinder. The structural basis for this highly complex protein packing is not known so far. Here, we report the electron cryomicroscopy (cryo-EM) structure of mega-hemocyanin complexes from two different snail species. The structures reveal that mega-hemocyanin is composed of flexible building blocks that differ in their conformation, but not in their primary structure. Like a protein origami, these flexible blocks are optimally packed, implementing different local symmetries and pseudosymmetries. A comparison between the two structures suggests a surprisingly simple evolutionary mechanism leading to these large oxygen transporters