Pyruvate carboxylase is expressed in human skeletal muscle

Pyruvate carboxylase (PC) is a mitochondrial enzyme that catalyses the carboxylation of pyruvate to oxaloacetate thereby allowing supplementation of citric acid cycle intermediates. The presence of PC in skeletal muscle is controversial. We report here, that PC protein is easily detectable by streptavidin blot and describe the presence of considerable amounts of PC in cultured human myotubes and in human muscle tissue.     

Huckebein is part of a combinatorial repression code in the anterior blastoderm

The hierarchy of the segmentation cascade responsible for establishing the Drosophila body plan is composed by gap, pair-rule and segment polarity genes. However, no pair-rule stripes are formed in the anterior regions of the embryo. This lack of stripe formation, as well as other evidence from the literature that is further investigated here, led us to the hypothesis that anterior gap genes might be involved in a combinatorial mechanism responsible for repressing the cis-regulatory modules (CRMs) of hairy (h), even-skipped (eve), runt (run), and fushi-tarazu (ftz) anterior-most stripes. In this study, we investigated huckebein (hkb), which has a gap expression domain at the anterior tip of the embryo. Using genetic methods we were able to detect deviations from the wild-type patterns of the anterior-most pair-rule stripes in different genetic backgrounds, which were consistent with Hkb-mediated repression. Moreover, we developed an image processing tool that, for the most part, confirmed our assumptions. Using an hkb misexpression system, we further detected specific repression on anterior stripes. Furthermore, bioinformatics analysis predicted an increased significance of binding site clusters in the CRMs of h 1, eve 1, run 1 and ftz 1when Hkb was incorporated in the analysis, indicating that Hkb plays a direct role in these CRMs. We further discuss that Hkb and Slp1, which is the other previously identified common repressor of anterior stripes, might participate in a combinatorial repression mechanism controlling stripe CRMs in the anterior parts of the embryo and define the borders of these anterior stripes.     

ConR: An R package to assist large‐scale multispecies preliminary conservation assessments using distribution data

The Red List Categories and the accompanying five criteria developed by the International Union for Conservation of Nature (IUCN) provide an authoritative and comprehensive methodology to assess the conservation status of organisms. Red List criterion B, which principally uses distribution data, is the most widely used to assess conservation status, particularly of plant species. No software package has previously been available to perform large‐scale multispecies calculations of the three main criterion B parameters [extent of occurrence (EOO), area of occupancy (AOO) and an estimate of the number of locations] and provide preliminary conservation assessments using an automated batch process. We developed ConR, a dedicated R package, as a rapid and efficient tool to conduct large numbers of preliminary assessments, thereby facilitating complete Red List assessment. ConR (1) calculates key geographic range parameters (AOO and EOO) and estimates the number of locations sensu IUCN needed for an assessment under criterion B; (2) uses this information in a batch process to generate preliminary assessments of multiple species; (3) summarize the parameters and preliminary assessments in a spreadsheet; and (4) provides a visualization of the results by generating maps suitable for the submission of full assessments to the IUCN Red List. ConR can be used for any living organism for which reliable georeferenced distribution data are available. As distributional data for taxa become increasingly available via large open access datasets, ConR provides a novel, timely tool to guide and accelerate the work of the conservation and taxonomic communities by enabling practitioners to conduct preliminary assessments simultaneously for hundreds or even thousands of species in an efficient and time‐saving way.     

Protective effect of resveratrol against doxorubicin-induced cardiac toxicity and fibrosis in male experimental rats

The possible effectiveness of resveratrol, a polyphenol present in different plants comprising berries, grapes and peanuts, on the prevention of doxorubicin-induced cardiac toxicity and fibrosis was investigated. Forty adult male Wistar albino rats were divided into four groups. Group I received normal saline, group II gavaged with resveratrol (20 mg/kg, daily for 4 weeks), group III received doxorubicin (2.5 mg/kg i.p. in six injections for 2 weeks; accumulative dose of 15 mg/kg), and group IV received doxorubicin?+?resveratrol (starting resveratrol intake 2 weeks before doxorubicin administration). Resveratrol significantly alleviated the increase in left ventricular lipid peroxidation, hydroxyproline, and tumor necrosis factor alpha levels as well as serum creatine kinase-myocardial band (CK-MB) activity and prevented the decrease in body and heart weights in doxorubicin-treated group. However, a marked protection against reduced glutathione content depletion and superoxide dismutase activity reduction was observed in the left ventricles of rats pretreated with resveratrol in combination with doxorubicin. Resveratrol also ameliorated the up-regulation of left ventricular caspase-3 and transforming growth factor-beta1 gene expression as well as left ventricular histopathological changes including necrosis and fibrosis induced by doxorubicin. Collectively, our results suggest that resveratrol provides a significant protection against doxorubicin-induced cardiotoxicity and fibrosis in rats. Therefore, it may be used as a promising cardioprotective agent in patients treated with doxorubicin due to malignant diseases. So, further clinical trials are required to confirm these findings.     

Phosphatidylcholine Supply to Peroxisomes of the Yeast Saccharomyces cerevisiae

In the yeast Saccharomyces cerevisiae, phosphatidylcholine (PC), the major phospholipid (PL) of all organelle membranes, is synthesized via two different pathways. Methylation of phosphatidylethanolamine (PE) catalyzed by the methyl transferases Cho2p/Pem1p and Opi3p/Pem2p as well as incorporation of choline through the CDP (cytidine diphosphate)-choline branch of the Kennedy pathway lead to PC formation. To determine the contribution of these two pathways to the supply of PC to peroxisomes (PX), yeast mutants bearing defects in the two pathways were cultivated under peroxisome inducing conditions, i.e. in the presence of oleic acid, and subjected to biochemical and cell biological analyses. Phenotype studies revealed compromised growth of both the cho20Δopi3Δ (mutations in the methylation pathway) and the cki1Δdpl1Δeki1Δ (mutations in the CDP-choline pathway) mutant when grown on oleic acid. Analysis of peroxisomes from the two mutant strains showed that both pathways produce PC for the supply to peroxisomes, although the CDP-choline pathway seemed to contribute with higher efficiency than the methylation pathway. Changes in the peroxisomal lipid pattern of mutants caused by defects in the PC biosynthetic pathways resulted in changes of membrane properties as shown by anisotropy measurements with fluorescent probes. In summary, our data define the origin of peroxisomal PC and demonstrate the importance of PC for peroxisome membrane formation and integrity.     

Vulnerability of European freshwater catchments to climate change

Climate change is expected to exacerbate the current threats to freshwater ecosystems, yet multifaceted studies on the potential impacts of climate change on freshwater biodiversity at scales that inform management planning are lacking. The aim of this study was to fill this void through the development of a novel framework for assessing climate change vulnerability tailored to freshwater ecosystems. The three dimensions of climate change vulnerability are as follows: (i) exposure to climate change, (ii) sensitivity to altered environmental conditions and (iii) resilience potential. Our vulnerability framework includes 1685 freshwater species of plants, fishes, molluscs, odonates, amphibians, crayfish and turtles alongside key features within and between catchments, such as topography and connectivity. Several methodologies were used to combine these dimensions across a variety of future climate change models and scenarios. The resulting indices were overlaid to assess the vulnerability of European freshwater ecosystems at the catchment scale (18 783 catchments). The Balkan Lakes Ohrid and Prespa and Mediterranean islands emerge as most vulnerable to climate change. For the 2030s, we showed a consensus among the applied methods whereby up to 573 lake and river catchments are highly vulnerable to climate change. The anthropogenic disruption of hydrological habitat connectivity by dams is the major factor reducing climate change resilience. A gap analysis demonstrated that the current European protected area network covers <25% of the most vulnerable catchments. Practical steps need to be taken to ensure the persistence of freshwater biodiversity under climate change. Priority should be placed on enhancing stakeholder cooperation at the major basin scale towards preventing further degradation of freshwater ecosystems and maintaining connectivity among catchments. The catchments identified as most vulnerable to climate change provide preliminary targets for development of climate change conservation management and mitigation strategies.     

Does the Effect of Micro-Environmental Factors on a Street’s Appeal for Adults’ Bicycle Transport Vary across Different Macro-Environments? An Experimental Study

Background

Characteristics of the physical environment can be classified into two broad categories: macro- (“raw” urban planning features influenced on a regional level) and micro- (features specifically within a streetscape influenced on a neighborhood level) environmental factors. In urban planning applications, it is more feasible to modify conditions at the neighborhood level than at the regional level. Yet for the promotion of bicycle transport we need to know whether relationships between micro-environmental factors and bicycle transport depend on different types of macro-environments. This study aimed to identify whether the effect of three micro-environmental factors (i.e., evenness of the cycle path surface, speed limits and type of separation between cycle path and motorized traffic) on the street’s appeal for adults’ bicycle transport varied across three different macro-environments (i.e., low, medium and high residential density street).

Methods

In total, 389 middle-aged adults completed a web-based questionnaire consisting of socio-demographic characteristics and a series of choice tasks with manipulated photographs, depicting two possible routes to cycle along. Conjoint analysis was used to analyze the data.

Results

Although the magnitude of the overall effects differed, in each macro-environment (i.e., low, medium and high residential density), middle-aged adults preferred a speed limit of 30 km/h, an even cycle path surface and a hedge as separation between motorized traffic and the cycle path compared to a speed limit of 50 or 70 km/h, a slightly uneven or uneven cycle path surface and a curb as separation or no separation between motorized traffic and the cycle path.

Conclusions

Our results suggest that irrespective of the macro-environment, the same micro-environmental factors are preferred in middle-aged adults concerning the street’s appeal for bicycle transport. The controlled environment simulations in the experimental choice task have the potential to inform real life environmental interventions and suggest that micro-environmental changes can have similar results in different macro-environments.     

The rust transferred proteins—a new family of effector proteins exhibiting protease inhibitor function

Only few fungal effectors have been described to be delivered into the host cell during obligate biotrophic interactions. RTP1p, from the rust fungi Uromyces fabae and U. striatus, was the first fungal protein for which localization within the host cytoplasm could be demonstrated directly. We investigated the occurrence of RTP1 homologues in rust fungi and examined the structural and biochemical characteristics of the corresponding gene products. The analysis of 28 homologues showed that members of the RTP family are most likely to occur ubiquitously in rust fungi and to be specific to the order Pucciniales. Sequence analyses indicated that the structure of the RTPp effectors is bipartite, consisting of a variable N‐terminus and a conserved and structured C‐terminus. The characterization of Uf‐RTP1p mutants showed that four conserved cysteine residues sustain structural stability. Furthermore, the C‐terminal domain exhibits similarities to that of cysteine protease inhibitors, and it was shown that Uf‐RTP1p and Us‐RTP1p are able to inhibit proteolytic activity in Pichia pastoris culture supernatants. We conclude that the RTP1p homologues constitute a rust fungi‐specific family of modular effector proteins comprising an unstructured N‐terminal domain and a structured C‐terminal domain, which exhibit protease inhibitory activity possibly associated with effector function during biotrophic interactions.     

<Emphasis Type="Italic">Ignicoccus hospitalis</Emphasis> and <Emphasis Type="Italic">Nanoarchaeum equitans</Emphasis>: ultrastructure,cell–cell interaction,and 3D reconstruction from serial sections of freeze-substituted cells and by electron cryotomography

Ultrastructure and intercellular interaction of Ignicoccus hospitalis and Nanoarchaeum equitans were investigated using two different electron microscopy approaches, by three-dimensional reconstructions from serial sections, and by electron cryotomography. Serial sections were assembled into 3D reconstructions, for visualizing the unusual complexity of I. hospitalis, its huge periplasmic space, the vesiculating cytoplasmic membrane, and the outer membrane. The cytoplasm contains fibres which are reminiscent to a cytoskeleton. Cell division in I. hospitalis is complex, and different to that in Euryarchaeota or Bacteria. An irregular invagination of the cytoplasmic membrane is followed by separation of the two cytoplasms. Simultaneous constriction of cytoplasmic plus outer membrane is not observed. Cells of N. equitans show a classical mode of cell division, by constriction in the mid-plane. Their cytoplasm exhibits two types of fibres, elongated and ring-shaped. Electron micrographs of contact sites between I. hospitalis and N. equitans exhibit two modes of interaction. One is indirect and mediated by thin fibres; in other cells the two cell surfaces are in direct contact. The two membranes of I. hospitalis cells are frequently seen in direct contact, possibly a prerequisite for transporting metabolites or substrates from the cytoplasm of one cell to the other. Rarely, a transport based on cargo vesicles is observed between I. hospitalis and N. equitans.